[MaybeStopCalling]

There's a reason AR-15 carbines have been the hotness for the last few years. Magazine commonality is high, accessories and parts are extremely varied and due to the modular construction of the rifle it can be drastically altered to fit the user. The P90 fills none of these.

Rethink your choice, please. Ditch the sidearm if it means you get a better primary- Every time I've had to pull my sidearm, it's been accompanied with terrified wishes that my primary was in my hands instead.