I am a big fan of the BPS but I think these guns are at their best in the field. The guns are well made and they shoot well but the bottom eject is difficult to single load for many people. Something more mainstream like an 870 Remington or better yet a M12 Winchester would probably be a better choice for the trap game.
I have a couple of BPS's and one of them is a trap model. My trap is from the 80's and has a selector, much like the new ones, to help ease loading of single shells. These are great shooters and recoil is mild for a light weight gun. The 30" barrel is plenty up to the task of trap shooting even back at the fence.
BTW, there is nothing more fun than shooting doubles with a pump gun!