To be honest I can't really say which one sounded warmer, and maybe that's not even the right word. And recently I've made several changes to my system; new cart, phonostage, and now the ATC HTS40's (like the SCM40's but a different enclosure), so it's difficult to say with any certainty. I would only say that I've owned many integrated amps and separates before, and have listened at audio shows and high-end retail stores, etc., and can attest to the great musicality of either unit. I guess my point was that either unit will be a top notch performer. Class A offers theoretical advantages but the Lux will run very hot; that I know.
I just think the Accuphase looks better, and I think your personal preference should at least be part of your consideration between these fine amps. Check out pics of my Accuphase in my virtual systems; it's called Music Is Magic
~Oran.