I have all my speakers set "Large" and the crossover at 80Hz. That is a personal preference, and is probably appropriate for my HT room and sounds good to my ears. Depending on what kind of setup you have, you may have to play around a bit to find what sounds best to you.

4 M80s/VP150/EP600/Denon AVR-5308 & DVD-2910/
2 QSC SRA3622(1100wattsX2)/Carvin 1800HD(600wattsX2)