IMHO the Black Scorpion Epic is more effective, as it is useful in PVP later on. I do not know, if you want to PVP, but with a NRG/NRG Stalker this would be an option.
I think going for Barrage is useless, especially slotting it. Get Energy Punch it does more DMG.
ESPECIALLY the Def-Buff in Hide is useless. It is true that you have a very high Defense with Hide, BUT you that only applies as long as you are "Hidden". Effectively, the high Defense automatically drops once you are noticed or you attacked, leaving you with such a low Defense Bonus given by Hide not worth noticing. Just slot Hide with 1-2 End Redu.
Personally, I am not someone who slots Health, I would pply put those slots in your Shields for Endu Redu, as a NRG/X Stalker is very Endurance heavy, even with an Endurance Drain and CP.
As you already played a NRG/NRG Brute, I thought you would slot Overload with 3 Recharge and 3 Defense Buff. It makes more sense I guess, as it is a Power like Elude. You are a Squishie with a Stalker, and when you hit your Tier 9 Power you DO NOT WANT TO BE HIT thus I would go for 3 Recharge 3 Defense Buff.
A build I came up with for ya, pure PvE though:
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Exported from Ver: 1.7.6.0 of the CoH_CoV Character Builder - (http://sherksilver.coldfront.net/index.php)
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Name:
Level: 50
Archetype: Stalker
Primary: Energy Melee
Secondary: Energy Aura
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01) --> Energy Punch==> Acc(1) Acc(3) Dmg(3) Dmg(5) Dmg(5)
01) --> Hide==> EndRdx(1) EndRdx(7)
02) --> Bone Smasher==> Acc(2) Acc(7) Dmg(9) Dmg(9) Dmg(11) Rechg(11)
04) --> Kinetic Shield==> EndRdx(4) EndRdx(13) DefBuf(13) DefBuf(15) DefBuf(15)
06) --> Assassin's Strike==> Acc(6) Acc(17) Dmg(17) Dmg(19) Dmg(19) Rechg(21)
08) --> Combat Jumping==> EndRdx(8)
10) --> Entropy Shield==> EndRdx(10) EndRdx(21)
12) --> Placate==> Rechg(12) Rechg(23) Rechg(23)
14) --> Super Jump==> Jump(14)
16) --> Swift==> Run(16)
18) --> Health==> Heal(18)
20) --> Stamina==> EndMod(20) EndMod(25) EndMod(25)
22) --> Build Up==> Rechg(22) Rechg(27) Rechg(27)
24) --> Power Shield==> EndRdx(24) EndRdx(29) DefBuf(29) DefBuf(31) DefBuf(31)
26) --> Energy Transfer==> Acc(26) Acc(31) Dmg(33) Dmg(33) Dmg(33) Rechg(34)
28) --> Aid Other==> Rechg(28)
30) --> Aid Self==> Rechg(30) Rechg(34) IntRdx(34) Heal(36) Heal(36) Heal(36)
32) --> Total Focus==> Acc(32) Acc(37) Dmg(37) Dmg(37) Dmg(39) Rechg(39)
35) --> Energy Drain==> Rechg(35) Rechg(39) Rechg(40) EndMod(40) EndMod(40) EndMod(45)
38) --> Overload==> Rechg(38) Rechg(42) Rechg(42) DefBuf(42) DefBuf(43) DefBuf(43)
41) --> Conserve Power==> Rechg(41) Rechg(43) Rechg(45)
44) --> Mace Beam==> Acc(44) Acc(45) Dmg(46) Dmg(46) Dmg(46)
47) --> Web Cocoon==> Acc(47) Acc(48) Hold(48) Rechg(48) Rechg(50)
49) --> Hasten==> Rechg(49) Rechg(50) Rechg(50)
---------------------------------------------
01) --> Sprint==> Empty(1)
01) --> Brawl==> Empty(1)
01) --> Assassination==> Empty(1)
02) --> Rest==> Empty(2)
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Thanks for the information, never realised about the def drop from hide so cheers for that will re-look at that. Only took barrage as wanted a quick attack power recharging at a lower lvl but will atke your advice and change it to nrg punch.
Going for GW Patron as wanted a snipe power and also the hold of Soul storm which sorry looks cool... 
With regards to Overload slots, even my Brute has 3xRechg and 3xHeal as this works better for me as a heal boost with other accolades stacked also, many discussions on which is better on the forums 
Sorry at work at moment or would pull some numbers up for you on the bonus's.
Nice build, but noticed you haven't taken energy protection any reason? Or was it just to fit in Hasten.
Thanks again for the info, guess not many people played the nrg/nrg stalker.
You are right, nobody play NRG/NRG.^^ I don't see why, it is effectively the only Stalker with resistances to Repel and Teleport.
Yes it does not have that many Defences, but my PvP Stalker on 50 (EM/SR) does not have that many Defenses as well, as I play it more hit and run. X/NRG has one thing going for it, Endurance Drain and CP! Every other Stalker has Endurance problems, but X/NRG can effectivly play without 'em.
I did not take Energy Protection as the resistances are pretty low and Stalker should be played (IMHO) without taking damage at all, not being able to take loads of it (I guess that is why I would slot overload on Def^^). You are right I wanted to fit in Hasten, for me it was essential, even though I already have a Recharge boost from SR.
Kaiser
PS
I think Black Scorpion is superior as its Hold has a -fly and a -jump component to it. As you cannot change your epic, this is definitely the choice to make for PvPing later on. And you get a decent sniper as well, which I put in the Build for ya 
Been reading your form post's and yes both are good builds but i have my own probs with little bit's and pecies.
[ QUOTE ]
ESPECIALLY the Def-Buff in Hide is useless. It is true that you have a very high Defense with Hide, BUT you that only applies as long as you are "Hidden". Effectively, the high Defense automatically drops once you are noticed or you attacked, leaving you with such a low Defense Bonus given by Hide not worth noticing. Just slot Hide with 1-2 End Redu.
[/ QUOTE ]
You say that this is not worth sloting with defence due to the drop that I cant agree with it is def worth sloting all be it later in lvl's.
Even in a PVE part of the game it is worth it due to being int large teams of 8 splash aoe damage from oncoming npc's with be dodged and evaded with the extra sloting.
Now in a PVP part of the game you will need it 3 slotted more of a need due to ppl using nasty aoe base moves so that they unhide stalkers.
4 sloting the power later in lvls best choice imo.
Next thing I think that would hinder both your builds is
slot alocation. My example of this is you Stamina you get this power at lvl 20 lvl 21 should be ample enough to 3 slot this power or energy transfer you started slotting that at lvl 31.
Here is a perposed build that will help u slot and understand slotting your powers.
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Exported from Ver: 1.7.6.0 of the CoH_CoV Character Builder
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Name:
Level: 50
Archetype: Stalker
Primary: Energy Melee
Secondary: Energy Aura
---------------------------------------------
01) --> Energy Punch==> Dmg(1)Dmg(13)Dmg(15)Acc(17)
01) --> Hide==> DefBuf(1)DefBuf(13)EndRdx(19)
02) --> Kinetic Shield==> DefBuf(2)DefBuf(3)DefBuf(3)
04) --> Power Shield==> DefBuf(4)DefBuf(5)DefBuf(5)
06) --> Assassin's Strike==> Dmg(6)Dmg(7)Dmg(7)Acc(9)Acc(15)
08) --> Build Up==> Rechg(8)Rechg(9)Rechg(11)TH_Buf(17)TH_Buf(19)TH_Buf(37)
10) --> Entropy Shield==> EndRdx(10)EndRdx(11)
12) --> Combat Jumping==> Empty(12)
14) --> Super Jump==> Empty(14)
16) --> Swift==> Empty(16)
18) --> Health==> Empty(18)
20) --> Stamina==> EndMod(20)EndMod(21)EndMod(21)
22) --> Bone Smasher==> Dmg(22)Dmg(23)Dmg(23)Acc(25)Acc(31)
24) --> Placate==> Rechg(24)Rechg(25)Rechg(34)
26) --> Energy Transfer==> Dmg(26)Dmg(27)Dmg(27)Acc(29)Acc(29)
28) --> Stealth==> EndRdx(28)
30) --> Energy Drain==> EndMod(30)EndMod(31)EndMod(31)Rechg(36)Rechg(37)Rechg(37)
32) --> Total Focus==> Dmg(32)Dmg(33)Dmg(33)Acc(33)Acc(34)EndRdx(34)
35) --> Conserve Power==> Rechg(35)Rechg(36)Rechg(36)
38) --> Overload==> Rechg(38)Rechg(39)Rechg(39)Heal(39)Heal(40)Heal(40)
---------------------------------------------
01) --> Sprint==> Empty(1)
01) --> Brawl==> Empty(1)
02) --> Rest==> Empty(2)
01) --> Assassination==> Empty(1)
---------------------------------------------
I consider slotting most important with it comes to a stalker and btw I could reduce my acc slot by 1.
As you have said you do hit and runs I would recommend you live by build up.
I also consider lvl 40 to 50 more an open choice. Hope this helps
Have decided to start a Stalker, and would like some advice from the Stalker population out there, as have only really played a Blaster and Brute also both Nrg/Nrg (Oh and a Troller) So please feel free to say what you think about the build i'm looking at and anything i should be looking out for, or changing
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Exported from Ver: 1.7.6.0 of the CoH_CoV Character Builder - (http://sherksilver.coldfront.net/index.php)
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Name: Soli
Level: 50
Archetype: Stalker
Primary: Energy Melee
Secondary: Energy Aura
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01) --> Barrage==> Acc(1) Acc(15) Dmg(17) Dmg(23) Dmg(37)
01) --> Hide==> DefBuf(1) DefBuf(3) DefBuf(5) EndRdx(11)
02) --> Bone Smasher==> Acc(2) Acc(3) Dmg(17) Dmg(23) Dmg(37)
04) --> Kinetic Shield==> DefBuf(4) DefBuf(5) DefBuf(11) EndRdx(13)
06) --> Assassin's Strike==> Acc(6) Acc(7) Dmg(7) Dmg(9) Dmg(9) Rechg(45)
08) --> Combat Jumping==> DefBuf(8)
10) --> Entropy Shield==> EndRdx(10)
12) --> Placate==> Rechg(12) Rechg(13) Rechg(15)
14) --> Super Jump==> Jump(14)
16) --> Swift==> Run(16)
18) --> Health==> Heal(18) Heal(19) Heal(19)
20) --> Stamina==> EndMod(20) EndMod(21) EndMod(21)
22) --> Power Shield==> DefBuf(22) DefBuf(25) DefBuf(29) EndRdx(31)
24) --> Build Up==> Rechg(24) Rechg(25) Rechg(27)
26) --> Energy Transfer==> Acc(26) Acc(27) Dmg(29) Dmg(31) Dmg(33) Rechg(50)
28) --> Aid Other==> Heal(28)
30) --> Aid Self==> Rechg(30) Rechg(31) IntRdx(33) Heal(34) Heal(34) Heal(36)
32) --> Total Focus==> Acc(32) Acc(33) Dmg(34) Dmg(36) Dmg(37) Rechg(45)
35) --> Energy Drain==> Rechg(35) Rechg(36) Rechg(39) EndMod(40) EndMod(40) EndMod(43)
38) --> Overload==> Rechg(38) Rechg(39) Rechg(39) Heal(40) Heal(42) Heal(42)
41) --> Moonbeam==> Acc(41) Acc(42) Dmg(43) Dmg(43) Dmg(45)
44) --> Soul Storm==> Acc(44) Acc(46) Hold(46) Hold(46) Hold(48)
47) --> Energy Protection==> DmgRes(47) DmgRes(48) DmgRes(48)
49) --> Conserve Power==> Rechg(49) Rechg(50) Rechg(50)
---------------------------------------------
01) --> Sprint==> Empty(1)
01) --> Brawl==> Empty(1)
01) --> Assassination==> Empty(1)
02) --> Rest==> Empty(2)
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