I recently added a 1500 series amp with 8 channels to my system. I had been running a 1400-8 since 2008, however some of the channels failed, more than once as the amp was upgraded and Axiom stood behind the amp all the way through the process and gave me a very generous option to upgrade from the 1400 to the 1500 series. I am running a Denon 3808ci receiver with a v2 7 channel Axiom ep80-qs8-vp180-800 system. Overall I have preferred the sound from the Axiom amp infinitely more than the Denon, in my room; however, the biggest difference I noticed was when the channels supporting the M80s died. There was just no contest in the comparison between the Axiom amp and the Denon internal amplification, it was killing me just to listen to how anemic it sounded. My surrounds I believe are mounted a bit high so I'm not clear about how important having the whole 8 channels driven by the digital amp is, yet my sense is that the soundstage seems more integrated with the 1500 amp driving all channels than when I had the Denon/Axiom amp combo in force.
"If you try to turn toward it, you go against it."