i cant comment on todays AVRs i have never really looked in to one, many years ago i think a 2 channel receiver sounded much better for music than a surround sound receiver set to 2 channel stereo, i have read several post on here recently that a AVR is great for 2 channel stereo
as far as sound quality between nice amps i will agree that you will probably get just as good sound quality with one brand Vs the next brand, how ever some brands have a better build quality than others and each brand will have a different sound. for instance Marants vs Cambridge vs NAD, they are all going to give you excellent sound quality, if you get a nice one, however one may have a warmer sound, one may have a brighter sound, one may have tighter bass, one may have more bosomy bass, ECT. you really should listen to some and figure out which one has the sound your looking for.
i think i have heard those speakers before and i remember thinking they sounded quite good, nothing wrong with getting a nice amp to run a nice small set of speakers. there is nothing like a good tower speaker but nothing wrong with a quality set of bookshelf speakers. i am so tempted to buy these mirage 0MD-15's crutchfield has for 1400.00 a pair right now. i have always been a huge fan of mirage speakers but i just got a set of definite BP8B speakers for 400 bucks on close out, usually around 1000.00 for a pair and they sound very good but not as good as the mirage speakers i used to have or have heard. i wish i was not at the point where i really should not spend any more money, i want those OMD-15's but i know i should not buy them, they will not be at that price for long so its hard not to pull the trigger on those even though it would be a bad financial decision. i need to pay off bills right now and not be buying more stuff no matter how hard it is to pass up.
Amplifier: Cambridge Azur 651A, Denon DRA 397
Speakers: polk TSX 330T, Definative BP6B, Energy C200
Music: Sonos Connect
Movies: Sony Blue ray player