Tech (= Cannot be dodged/shielded = Guaranteed hit)
Elemental Damage (= Armor does not apply)
100% proc chance on CGC (= A heavy DoT + Snare)
2.0 sec cast time, 1.5 with talent.
Ranged (= Can be dodged/shielded = Not a guaranteed hit)
White Damage (=Armor applies)
No 100% proc chance on CGC
some small things to concider. powershot does'n need to hit to proc ppa. is just needs to be casted (deflect or not doesn't matter, nor does shielding).
also even if regular armor is ignored by flameburst, everyone still has at least 10% dr against it. (marauders with cloak of pain on have between 34 and 37% dr against elemental damage and there are a lot of thoses)
that beeing said fb is superiour for proccing since it can be cast on the run and cannot be interupted through kb stun or regular interupt.
dps wise though powershot is 2100 vs flameburst 1300 damage, so the enemy would need to have around 50% damage reduction to make blameburst deal more damage and even more if it is a marauder.
and don't forget shroud, that completely negates flamburst and incendary missile while removing all dots (making it almost impossible to railshot for a pt), while a powershot still can apply a dot through shroud and then railshot the shrouded assasin