This gun feels incredibly goofy to use at the start but you'll find that it's actually a quite solid weapon with the right build. It has multiplicative GunCO so your damage potential is pretty impressive if you have any additional source of priming. You can switch the build around to corrosive + heat if you have an external source of viral priming and [Pistol Elementalist] can be interchanged with [Magnetic Might] if you prefer the extra element to the the nuclear heat procs provided by elementalist.

EVO 2:

Rapid Wrath (+25% Fire Rate)

EVO 3:

Rapid Reinforcement (+30% Reload Speed)

EVO 4:

Lethal Lance (On Kill: +2.5 Punch Through for 20s)

EVO 5:

Impaler's [Ferocity] (On Punch Through Hit: +200% damage for 10s)

We choose those two 4 and 5 evos as they provide an ample amount of base damage which saves us a mod slot/Arcane slot. Punch Through is also fun. Devastation Cascade is a potential choice but with the addition of Enervate it is sort of redundant and does not provide buffs to the whole build, only the Incarnon Mode.