One thing that differentiates dedicated power amps from AVR's and is mentioned regularly is the REAL power ratings when ALL channels are driven at the same time. Power amps give you all the rated power but most AVR's list power per channel usually with only ONE channel driven. When all are driven at the same time the actual levels can drop significantly. I am currently running a Yamaha receiver (pre-out) into two Outlaw multi-channel power amps with the eventual desire to buy a pre-pro from Outlaw, Emotiva or even Axiom should they eventually decide to offer one. I can't honestly say that the separate amps were significantly better than the internal amps in the Yamaha but separate power amps never go obsolete and they are much more flexible when it comes to handling speakers of varying ohm ratings.
