separates better?
I have very limited experience here but I just bought a separate amp and can share my listening experience. I think that the overwhelming consensus is that separates are better....that being said, I think it depends ultimately on if your speakers (and input) will justify it. I have a Yamaha RX-V2600 (130wpc) which seemed OK last year with Klipsch RF-5 in front of my 5.1 HT system. I upgraded to the RF-7 (a very large speaker system) and moved the RF-5 to the rears. The yammi certainly was "loud" (powerful) and "detailed" enough...it is a fine receiver...but I didn't think I was getting what I had expected from a much better front speaker. I added a Rotel RB-1080 to drive the RF-7 front and the difference was very noticeable. Mid-range came alive with a lot more detail and bass improved (not the sub frequency but the middle to low). I don't know if the difference was from increased power (200wpc) or the improved performance of the separate amp and I'm sure everyone will have an opinion on that. I think it's both and I think the difference will be unique to sets of speaker driven. For the comparison, I listened to both set-ups in two-channel mode, balanced by SPL to same listening level and the Rotel was clearly better. Knowing that, I'll base future upgrades on developing a component system with separates.
(BTW: I'm mostly listening to music on CD, DVD 5.1, or DVD-A...whatever happens in movies is a bonus)
Hope that helps you a little.
Roger