I've never really noted the M500 as OP, but the M500SV (which I have used) does have the highest accuracy (58 if I remember correctly), giving it a better consistency, at the cost of rate of fire. In that sense, it's a bit of a min-maxer, and perhaps more suited as an option to unlock later. As for the Pentagun: it's got a pretty high DPS. For each 202 damage shot from my PM5, it can do two 170 damage shots, for a nice 340 damage. Granted, it is a semi-auto, but perhaps it's not such a good idea to let the new players get their hands on semis so quickly.