Traps vs Traps vs Devices?
Doing a direct comparison isn't really feasible since the two sets are very different. Traps is a Buff/Debuff set while Devices is a Manipulation set.
From a strict numbers point of view Traps is superior but you could say the same about comparing any Buff/Debuff set to a similar Manipulation set.
The question then becomes how do they rank against other sets of the same type? Traps is generally considered one of the best Buff/Debuff sets for solo play and is a very strong set for team play. Devices on the other hand is generally considered one of the weakest Manipulation sets, it trades quite a bit of damage compared to other Manipulation sets but doesn't really get much in return, it offers some survivability but Ice Manipulation provides similar benefits along with more damage.
That isn't to say Devices is useless, it can be a lot of fun to play especially if you enjoy soloing and are willing to spend some time setting ambushes and it isn't useless in team play although you won't get as much benefit as some of the other manipulation sets. In the case of DP/Dev this is made worse by the fact that DP is on the low end damage-wise compared to other Blast sets.
DP/dev can be fun if played solo. If you are on a team you will feel like you secondary is basically useless. Traps on the other hand always make a team better, and performs very well solo. I run and all dual pistols ST on Thursdays and we have a Traps def who make AVs cry for mommy. As Adeon said, DP is on the lower end of the damage scale, so I lean more towards Corrs for DP. If you plan on playing more solo, I say DP/traps corr, if you are geared more towards team play, traps/DP def for the better buffs/debuffs.
I've got a couple device blasters, and tried out all the powers. Devices is a unique set, very different from the other secondaries. I'd recommend it more for players who've already tried the other secondaries and are looking for something different.
It does some cute things that are fun to use, however it is missing the real meat-and-potatoes of the other secondaries. Until devices gets REAL compensation for the lack of buildup, it will forever remain "that quirky set that does funny things on the side."
Traps is great fun though. Even on fast moving teams, I love dashing into the center of enemy groups and dropping a poison trap. Acid Mortar, as with anything that debuffs resistance, is great. And who doesn't love more defense that doesn't deactivate if you get mezzed?
The Bacon Compels You.
I'll second the unique play style of devices. My DP/Dev blaster has been the only blaster I've ever enjoyed (let alone tolerated) soloing on.
With smoke grenade and cloaking device (and someone's advice to play /dev as a primary) the mayhem that can be caused with caltrops and trip mine is a blast. I'm considering time bomb just be able to plant it in the middle (well, just behind) of a spawn to blow it into to my nice mine field. I already do this with a trip mine but it detonates right away so I can't move to somewhere with a better view before it goes off.
You'd need a team that accepts you as basically a ranged stalker who can scurry off and prep the next pull for instant demolition as the current one is being finished off. Steamrollers would basically shutdown /dev. Non-conventional teams could be very entertaining though.
I've settled on making a Dual Pistols...something. The issue I'm running into at the moment is which AT to pick. I'm aware the debuff and buff values will be higher for a defender, and damage will be higher as a Corrupter, but I'm curious how Devices stacks against Traps. I know a few powers are different, such as the turret and the little accuracy boosting toggle, but I thought I'd field the question to get some opinions.
Also, if anyone has some tips on how DP and traps/devices work together and some common tactics, that'd be great. But not necessary.