I was really looking at getting the 600, but all of the tests that I seen on the 600 were inconclusive. Plus another deciding factor was the Pre-Order price which was something like $150 or so off of the normal price. Without the pre-order price, it was still cheaper then the 600.

Receiver: Yamaha RX-V2200
Main: Axiom m80
CC: Axiom VP150
Surround: Axiom QS8
Sub: SVS PC13-Ultra