I have a Sony STR-DE825, and recently bought a pair of M60s.
First, don't worry about your receiver "getting in the way" of the speakers. The speakers will sound great. Not to say I wouldn't like to upgrade my receiver at some point in the near future, but the receiver certainly does the speakers justice.
Secondly, dialog coming from the center channel is often much quieter than the "action" (explosions, etc.) that comes from the other channels. DVDs soundtracks can be very dynamic, mimicking the movie theater experience. If you want to counteract the sudden changes in volume, use the Dynamic Range Compression on the receiver, or raise the volume level of the center channel a bit.
Just my $.02.
Scott
