On a Defender in PvP? No.
I would stick with the rad pain and mix up your build some. Get as many hp as you can and some +damage. Pain dom is a way underrated set by most people. It gets very nice resistance +tohit and +damage. The regen is very nice even in dr pvp. A good pain dom is next to impossible to kill without being way outnumbered.
Duel me.
I will work on my sig pic more when I have time.
(You can skip this middle, it's just backgound)
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I've been trying to come up with a powerset for a character by the name of VhampiR. Obviously the theme here is darkness. (Red also good, blood-like.) I've already tried her as multiple builds, current one is Rad/Pain Corr. (Trying to keep it villain)
Anyways the build I had planned wasn't going to be fairly expensive (only 1 purp set, the Ranged dmg for the Regen Bonus, used twice. 3 each in 2 different powers.) and was based off of getting as much regen as possible. I chose rad for the stun in cosmic burst, so it would be applied fairly regularly. But after remembering that DR would hit regen hard, and after every attack/summon/heal you get yet more heal decay. So perhaps that 41 hp/sec I had built up in Mid's wasn't going to equal much. So, what else does pain really have to offer but a melee debuff and ally buffs? (I'm more along the solo pvp, though I team in zones, I tend to forget to buff my team-mates)
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(So, about the title question)
I've been looking at radiation emission. (The defender side.) I thought with a modified debuffs on defenders and paired with dark blasts (also with boosted -tohit from def mods) I might get an equivalent to decent defense. With DR and the mez system, is this still anygood? What would -48% tohit be about in a zone? How well do dark blasts stack? Does power build up used before radiation infection effect it the whole time, or just for its duration? (looking at FF here and how the pb'ed shields work) Will Rad Infection and Enervating Field really be knocked off me that much to where its pointless? More so in arena or zones, are they the same?
Yes, that's a lot of questions, but I would really hate to have to delete VhampiR yet again for another build, or perhaps take her out of one thats actually good, and I'm just going about it wrong. (For those who didn't read the middle, she's a rad/pain corr)
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Anyways there's my question that basically can be summed up by "Is Radiation Emission still worth it on a defender?"