When you pick dark/dark, its definitely a hell to play. low endurance, lots of MUST take powers (acro, thats 3, stamina, thats 3).
Forget about the AoE fear, it sucks, and costs WAY tomuch end, you cant really take that much end.
Dark/Dark takes a special kind of people to play. which makes sure that if you've gone through the hell that is 50 levels of dark/dark. You're sure to be proud, and love you character.
Sadly i havent played in a few months, so im not sure of any recent changes.
In short:
- Watch your endurance
- Plan you build on endurance first, then on defence, then on attack (sherksilvers hero builder does the job quite nicely)
- Kick [censored]!
- It's not easy to play well, but when played well, its a force to be reckoned with 
@Shift
Shift 50 DM/DA Scrapper ][ TTL 50 Kat/Reg Scrapper ][ Shabriel 50 Peacebringer ][ Ion Shift 46 Rad/Rad Corruptor ][ Thermal Shift 35 Fire/Fire Blaster
"A Scrapper is a lot like a chainsaw. Somewhat hard to handle, incredibly dangerous, and by far the most fun when wielded by the slightly insane."
All this would seem to explain why DM / Regen is quite a popular choice. /regen gives you QR for mitigation against endurance issues, and Integration for built in mez and knockback protection.
The irony of having to take Acrobatics with /DA, is of course it in itself is a big end hog as well!
@SteelRat; @SteelRat2
"Angelina my love, I'm a genius!"
"Of course you are darling, that's why I married you. Physically, you're rather unattractive"
http://faces.cohtitan.com/profile/SteelRat
I can't comment of the Primary, but /Dark is sometimes hellish to play. As others have said, Endurance will be your biggest burden as it's mostly all toggle based. However, I tend to think of it as a Swiss Army Knife of secondaries. You've got resistances to just about everything apart from knockback so often you will have to play about with which toggles you need for which situation.
The best advice I can give for /Dark is to keep your toggles on a separate toolbar and consider which ones you need for the foes you are facing. Turn on the ones you need and turn off the ones you can do without. It matures later but you will need patience to persevere with it. Good luck! 
@Dante EU - Union Roleplayer and Altisis Victim
The Militia: Union RP Supergroup - www.themilitia.org.uk
Myself and Shift were the 1st lvl50 DM/DA scrappers on EU servers, and a lot of changes have been made to the powersets since.
The powerset is a hard struggle to 50 and takes a lot of hardwork to play efectively. but as soon as realise the potential of it, you can waltz through most mobs at ease.
Stamina is a must power, with the recent changes and my current slotting i can now have my 3 main shields on with cloak of darkness and cloak of fear running. ( i love the AOE fear, and will not respec it out)
i can post my build if required??
Yeah yeah, please post it ^^
I love my dark/dark endurance isnt too much of a problem with dark consumption I think its called which is a pbaoe attack that drains health from mob around you and gives you hp (I think ^.0) So with that you wont struggle to much. Also I didnt take acro I do fine without it mostly but I can imagine it is helpful
Powers not in order of taking them.
Dark Melee
Smite - acc2 dmg2 endred2
Shadow Maul - dmg3 endred2 acc1
Shadow Punch - dmg3 endred2 acc1
Soul Drain - dmg4 endred1 acc1
Midnight Grasp - dmg4 endred1 acc1
Dark Consumption - acc1
Dark Armour
Dark Embrace - dmgres4 endred2
Death Shroud - dmg2 acc1 engred1
Obsidian Shield - dmgres4 endred2
Murky Cloud - dmgres4 endred2
Cloak of Darkness - defbuff2 endred2
Cloak of Fear - endred1 tohit1 acc2 fear1
Regeneration - acc1
Hasten from speed pool
Hurdle, Health and Stamina from Fitness pool
A few minor changes with slotting will be done sooner or later, but i'm quite happy with how my character performs.
Ah dark/dark, you're right that it's not common, but not necessarily that it's no good. Everyone you ask will have a different opinion and pretty much all of them will be valid, so expect to see contradicting advice. It's caused me the biggest headaches, the most anguish, but also the best moments of my time playing CoH.
Let's start with the minuses...
1) No knockback protection
Not the end of the world, and you don't have to take some, but going up against avalanche shamans will make you want some! Acrobatics is best, and combat jump can be used as immob protection instead of Cloak of Darkness if you take jumping. If not, take hover.
2) Can't...breathe...
The endurance demands of dm/da are so great that you may well forget you have a blue bar! It is possible to go without stamina, but it requires hard slotting in the right places. Dark consumption is a top power, but the to-hit requirement makes it hard to rely on that power alone. I'd suggest trying with and without stamina, as it is do-able, and sans stamina gives you a good feel for the sets in their truest form. Having said that, you WILL take stamina!
3) Strange attacks
Ok, it's a strange set so you might expect something a little different, but what I'm trying to get at is that your attacks seem under powered because they all do other things. You have two attacks that also heal(siphon life and dark regen), and one that regains End(dark consumption) and a tight cone attack that roots you for what seems like a lifetime. The attacks in Dark Melee are unlike any others in the game.
4) Dark...Armour?!?
The protection that dark armour gives isn't like proper armour, it's more damage mitigation. More informed souls than I have written better explainations on this subject than I ever will. Basically, every power works to stop you getting damage, whether through resistance, dropping baddies quicker (death shroud), fearing your foes (cloak of fear) or disorienting minions (oppressive gloom). The hard part about this is getting your head round how you can best use these powers to your advantage.
And now the good points...
1) Shadow Maul
Ok, ok, it uses a ton of End, and ok it roots you for an eternity, and yes, you do have to maneuver baddies into a line... but OMG it's an amazing feeling when you drop 4 mobs at once with this amazing attack!
2) Soul Drain
This for me is possibly the best power in the game. I've heard people complain that they don't feel that super when they play CoH, this will change your mind. Having struggled to 26, this power damn near changed my religeous beliefs! Imagine a build up that lasts for 30 seconds, gets better for every mob it hits and actually does damage as well! It's also there every fight to give you glowy goodness
3) Fear me...Fear meeeeeh!!!!
Cloak of fear is the cause of all your End problems but can also be your salvation. Fears minions and lieutenants and stacks with touch of fear to make bosses quake in their boots. Team with mind or illusion controllers and rule!
4) Oppressive Gloom
Practically 0 end use and a minor hp tick for every minion it hits make this a great control to keep you safe and the baddies close. Ok so it's only hitting minions, but who cares when a power is this good?
And finally...
I'm guessing if you're posting on the boards, you're already pretty au fait with CoH, which is a good thing if you're going to go ahead with DM/DA. All I have left to say really is do research, there are a few good guides out there which will help lots(DM/DA Bible). It's a hard combination to pull off, but is lots of fun and can make you feel "uber" if there is such a thing any more. Do persevere with it, but be prepared for some out of the box thinking (sorry for the cliche!).
Good Luck!
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Psy Patch 36 mind/rad controller
IcePatch 35 ice/kin controller
NightRay 32 dm/da scrapper
SpinePatch 36 spines/da scrapper
FrozenPatch 25 ice/em tank
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[ QUOTE ]
Team with mind or illusion controllers and rule!
[/ QUOTE ]
Yer but we Illuz don't need anyone else to rule /em muahahaha.
... Errm soz, New Year's Eve hangover 
My 1st ever character was a DM/DA scrapper and I chose those simply because they sounded fun. That was around 10 months ago and because I have altitis he is still only level 26 (still my highest level toon tho).
Having now played other characters I admit that DM/DA does have a unique "feel" to it compared to any other combos and does take getting used to but it is worth perservering.
I have not found endurance to be a huge problem leveling him so far but I did take Stamina by level 20 (it really does help)
Cloak of Fear sounds like an uber power and in some ways it is but endurance wise its a glutton. I personally get by just using fearsome stare to lock down more dangerous enemies while I pick off the followers.
Also, there is a mentality in scrapping to attack the "biggest baddest boss" in the fight. DM/DA does not excel at this but it is unsurpassed in taking down whole swathes of minions and LTs faster than almost anything else in game.(useful for your XP that! 
)
I would also agree with the earlier post about checking out the DM/DA bible. Not sure how current it is now (around I7ish?) but even so its a superb guide that gives comprehensive reviews of the powers and a number of builds.
So there ya go, just a few observations of mine there that hopefully may prove useful for you. Either way can I finish by saying that I hope you have fun dealing the damage of the Dark!
Cheers
Hey can i suggest doing a Duo with someone you play extremely often with.
Cos i Duo with my mate Arctic Sheep as you know our lvl 50 sheep
were now doing he a kin/psi def n me a kat/invul scrapper so i can have like 9 toggles and not need to worry about it.
get a friend or a mate on coh to make like an empath defender or something to give you endurance, you'll enjoiy the game so much more with lots of endurance =]
[ QUOTE ]
[ QUOTE ]
Team with mind or illusion controllers and rule!
[/ QUOTE ]
Yer but we Illuz don't need anyone else to rule /em muahahaha.
... Errm soz, New Year's Eve hangover
[/ QUOTE ]
Yer but we darkens don't need anyone else to rule
Honestly I don't think that Dark/Dark has endurance issues at all. With Dark Consumption 6-slotted and Stamina you have the potential of an energiser bunny.
Seriously, the only real end hogs in the set are Dark Regeneration, Death Shroud and Cloak of Fear (Cloak of fear being sub-par compared to Oppressive Gloom for 95% of normal gameplay) and if you stick two endred SOs in each of those powers then they're perfectly manageable. Your armour toggles are reasonably low-cost and perform well with only one endred SO, though acrobatics could do with two endreds if you decide to take it.
You want endurance problems? Try rolling a Spines/Dark... I'd KILL for Dark Consumption!
I could see BS/Dark having big end issues as well.
Defiant 50's
Many and varied!
@Miss Chief
I rolled my spines/DA scrapper as a concept build after getting my dm/da to 30. All I can say is, fastest levelling toon I've had so far, but most of all lots of fun to play
I'm thinking of writing a guide as I haven't seen one out there, I'll get started on it if there's a demand for one.
With regards the high End use, Cloak of Fear's your biggest drainer, so I'd test it out before getting it. With DM/DA, you can use dark consumption to offset this drain. A typical tactic is to run in with death shroud and cloak of fear (and oppressive gloom ), soul drain, touch of fear, dark melee, smite, and when they're low enough, use dark regen and dark consumption to top up health and stamina and finish off the last few mobs. You soon get an idea of when they'll die and you need to get dark consumption in before they drop. You also learn quick to avoid high defence baddies (crey) and acc debuff baddies (CoT).
There are always discussions about getting Death Shroud and cloak of fear and whether they counter each other. In my experience, cloak of fear still drops the incoming attacks by at least half, plus the acc. debuff makes them less likely to hit, and death shroud with soul drain is a pretty impressive power. Bear in mind also that death shroud keeps ticking even when you're hit with a -recharge.
Dark/Dark was my first toon ever on CoH and I still love him (eventhough he wasnt my 1st 50).
Acouple short comments:
Cloak of Fear vs. Oppressive Gloom: I found that Oppressive Gloom as mentioned earlier is more usefull for most of the game and it affects some baddies that Cloak of Fear doesnt. Plus, the low end. with Gloom compared to Fear is a nice bonus. **I just couldnt find room for both 
Mastery: My first go around I went with Dark mastery to fit my character better and the Petrifying Gaze helped quite a bit from time to time; however, due to end. problems i tried a new mastery--Body. Conserve Power, Focused Accuracy with Hasten thrown in is very nice. -- What Dark Consumption didnt hit target(s)? well, Conserve Power, Hasten and by the time conserve power is running out Dark Consumption is almost ready again.
All the time Siphon Life and Dark Regeneration keeping me alive. Can almost take out a turret in RV by the time my slow heavy arrives on the scene.
@Cha'ron:
Cha'ron-lvl50 Controller
Votary-lvl50 Scrapper
Logan W-lvl50 Scrapper
Destrer-lvl50 Tank
Panade-lvl50 Defender
@Tellur:
Tellur-lvl48 Controller
www.theultimateinferno.com
Its not a common build, and that probably means isnt good, but i was thinking to try it cause i like dark powers and because im tired to only see /regen people, and i dont wanan become a clone.
My dark/dark is only lvl 8, so i cant say much about it yet... but taking a look on dark powers, i've notice dark armour seems to be great because offers all protections (particularly psionic, fear and confuse too) and it has a aoe fear attack too. i just dont like ultimate power (i've never tried, but it doesnt seem great..) and fact you dont get knockback res --__-- so... i think i'll absolutely have to get acrobatic, that means SJ as travel power... no choice..
Talking about primary, it seems cool again (- acc effect rocks, particulrarly in pvp) but it doesnt offer regular build up O_o and again, final power doesnt seem great so...
im still not sure if use this dark/dark scrapper or delete him..
i how powers looks like but i would like to know they're good too :P