There are environments where the four π's work better, but if you have two suitable corners, the seven π's almost always win out. The corners help enforce the bass and sound is uniform throughout the room at all frequencies. But I think both the Theater four π and seven π speakers are great sounding.

You might also consider Theater seven π cornerhorns with an additional midrange horn such as the one I've just developed. I'll be showing it any day now; It's tested and ready to go and now I'm just waiting on a pair of more attractive models to get back from the wood shop so I can click some photos.