No experience on RAD primary so telling you what i think of secondary.
You got stamina and AM.With hasten it is near pear hasten + AM so you recover endurance like crazy and use it like theres no tomorrow.
RI: you can afford its end without End Reducers.Better more Def Debuff there
LR: six slots no doubt.More recharge.
EF: you can live with just 1 end redux.
RA: six slots 3 rec 3 heal(forget end redux here-with sta + AM it will recover the difference of slot it or not in 0.6 sc)
Mutation: i like it in PVP(just personal preference).Useless for PVE.Most ppl would say: skip it and they are probably right.
Fallout: i think it is not good enough in PVP nor PVE.If you choose to include in your build for PVP 3 ACC or its useless.
Choking cloud: 4.16 EPS....you CANT afford this.STA+AM cant do nothing about it even if you End Rex on it.If you use it as a click power instead of a toggle its long recharge,low % of hold and low mag makes it of no use.
GL and meet you on top of Grandville. 
advice / suggestions please.
Name: Emanator
Level: 50
Archetype: Corruptor
Primary: Radiation Blast
Secondary: Radiation Emission
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01) --> Neutrino Bolt==> Acc(1) EndRdx(3)
01) --> Radiant Aura==> Heal(1) Heal(13) EndRdx(17) Rechg(43) Rechg(46)
02) --> Irradiate==> Acc(2) Dmg(3) Dmg(7) Dmg(11) Acc(15) Rechg(15)
04) --> Accelerate Metabolism==> Rechg(4) Rechg(5) Rechg(5) EndMod(17) EndMod(25) EndMod(45)
06) --> Radiation Infection==> EndRdx(6) TH_DeBuf(7) DefDeBuf(13) TH_DeBuf(34) TH_DeBuf(36) EndRdx(37)
08) --> Hasten==> Rechg(8) Rechg(9) Rechg(9)
10) --> Enervating Field==> EndRdx(10) EndRdx(11) EndRdx(36)
12) --> Swift==> Run(12)
14) --> Super Speed==> Run(14)
16) --> Health==> Heal(16)
18) --> Cosmic Burst==> Acc(18) Dmg(19) Dmg(19) Acc(29) Dmg(40)
20) --> Lingering Radiation==> Acc(20) Acc(21) Rechg(21) Rechg(25)
22) --> Stamina==> EndMod(22) EndMod(23) EndMod(23)
24) --> Mutation==> Rechg(24)
26) --> Neutron Bomb==> Acc(26) Acc(27) Dmg(27) Dmg(29) Dmg(31)
28) --> Aim==> Rechg(28) Rechg(46)
30) --> Electron Haze==> Acc(30) Acc(31) Dmg(31) Dmg(34) Dmg(46)
32) --> Atomic Blast==> Acc(32) Dmg(33) Dmg(33) Dmg(33) Rechg(34) Acc(43)
35) --> Choking Cloud==> EndRdx(35) EndRdx(36) EndRdx(37) Hold(37) Hold(43)
38) --> EM Pulse==> Acc(38) Acc(39) Hold(39) Hold(39) Rechg(40) Rechg(40)
41) --> Charged Armor==> EndRdx(41) DmgRes(42) DmgRes(42) DmgRes(42)
44) --> Power Sink==> EndMod(44) EndMod(45) EndMod(45)
47) --> Electric Shackles==> Acc(47) Acc(48) Hold(48) Hold(48)
49) --> Fallout==> Acc(49) Dmg(50) Dmg(50) Dmg(50)
---------------------------------------------
01) --> Sprint==> Empty(1)
01) --> Brawl==> Empty(1)
01) --> Scourge==> Empty(1)
02) --> Rest==> Empty(2)
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