I have had some quite incredible subs through my room (in both sound quality and quantity) and with poor placement, it simply doesn't matter. You can get weak, nonexsistant, sloppy bass out of even the best of subs if you don't place them right.

I can't tell you how they will integrate with your 4 pi's because I don't know what your room setup is like. It depends on corner or wall placement, the location of the sub and the location of the listener.

The best way to do it is to place the sub in the spot where you will be listening from, and walk around the room until you find a spot where the bass sounds the best. Then put your sub there.

All depends on your room.

Adam