I voted for the SMG. It looks so cool, and stands out more than the Microwave Gun. Greg Broadmore, the man who created all the weapons for D(, has said that the SMG is his favorite weapon. That's gotta count for something, right?
I'm still hoping they might possibly come out with the Sonic Wave gun. It was the most used weapon in the move, next to the Arc Generator/Assault Rifle. I think they are going after weapons they made molds for. I believe the SWG was a one-off, so it doesn't look good for it being made into a replica.