I've been following this thread for quite some time. Let me first say that I am a very happy owner of an xa-30.5 - great amp with my 94db speakers.
To me, Audiofeil's statement clearly sounds like a dealer trying to aim for the sweetest price point. Rather than a sign of any hidden truth or anything similar it is the mark of a shrewd dealer. Whatever.
With regards to the issue at hand, I think that given that Roor has Totem speakers (4ohm, not very efficient) - his preference for the xa-60.5 makes a lot of sense. If I owned his speakers, I would have opted to try the 60s first.