Overpowered?
The range is small: almost all good weapons have a better range, only Pancor and HKP90 don't do better
The damage are low: 39 average on a Combat Armor; a Rocker Launcher does 62
I'd love to use this weapon, but I think the drawbacks are too importants.
Or maybe lower the splash (same as Rocket Launcher) and raise the range.