I have listened to them both, but found myself at the Analog Room in San Jose listening to Ayre separates, among others (given your handle and components, I'll assume you live near the San Francisco Bay area). I was stunned at the quality and clarity of the Ayre pre/power amps, but walked out with the Cayin A88-T integrated.
This is going to sound hard to believe, but I felt the Cayin sounded better than McIntosh separates to me, and more musical/less clinical than the W-6 (although the I-5.3 has always impressed me).
Through a set of humble Quad 22L speakers, the Cayin equalled most of the other high end gear onsite. I realize this is all subjective, but I was absolutely blown away... and handed them my money.
I understand it can be used as a power amp as well - check it out.