Tried the Locust on Gold - still sucks. I can't even really call it a caster weapon; Either you easily outdamage it without firing a shot (biotics) or you have the capacity for heavier, and much better, guns anyway (engineers/sentinels). I guess it's nice leveling up before you have your passive but once you can carry something heavier, toss it.

I have my Fury carry it (it still looks pretty sexy) but it gathers dust at her hip.