I would like to know how they sound with Axiom. I can same $$ getting that, otherwise for a bit more I'm looking at a Nad T744, or a Cambridge Audio 540R v2.

Just going with the brand names it sounds so much cooler and worth the $$ to have a Nad or Cambridge Audio, in particular the Nad for me

I had the XR-55 and it sounded great! The only reason I switched to the Pioneer VSX-817 was for the MCACC utility which gives me more flexibility. The XR-55 only had bass and treble control. Not sure if the XR-57 is much different in that area.