And would it be a useful weapon at all, i know it may be pretty hard to determine its real life power, due to the fact that fallout new vegas is a game and all, but would it serve any purpose at all, or would it just be some kind of gimmicky weapon that should stay in fallout?

I would say so, if they could fire with just a detonator of some sort like Euclids C- Finder. Could destroy entire units in one hit. (Or an army )