Usually ATI amps or amps made by ATI (Outlaw, Monoprice). Also Anthem, Parasound, Rotel.
It might seem funny, but it seems the OLDER I get, the more I gravitate toward just using AVR and not using external amps, except for my 12 passive subwoofers which require external amps.
I started out in this hobby using AVR. Then very quickly went to separates for most of my life. Then now that I am 51 YR old, I am gravitating back to AVR. Probably means I am getting OLD.
But I still have my Yamaha AVP and amp and ATI 200WPC amp. No reason to change right now.