I'd suggest staying away from the 3 1/2". I had a few pheasant hunters at my place shooting them this year, and when shooting 2 3/4" shells they short shucked their guns all the time, they will eject the shorter shell, but the action isn't opened all the way so they closed the action on an empty barrel.

I've had a few BPS Stalkers in 3.5", I never bought them, I won them. They would also short shuck shells, and finally I got tired of it and sold all of them.

If you can afford a BPS, it might be a better an safer route, as you won't have a backwards safety and the shells are being ejected out of the bottom.