I have had Pioneer SA-9100, Marantz 1060, Denon PMA 250, and Sony TA-1130. I still have the TA-1130 and love it. I wish I still had the SA-9100. I would jump at the opportunity to own a Kenwood KA 600 or a Sansui AU 999.
I let go of the Pioneer due to NUBENESS (ouch). I was matching that amp with Klipsch kg4s. All I can say is that is a bad idea. I would love to hear it through my ADS 1230's. Too bad, so sad, too late.
I have to say that from my listening experience with the various match ups I have had I like the Sony TA-1130, but the post asks for what is your favorite. I guess the war between dual mono Power Kenwood KA600 or smooth tube-like sound Sansui AU999. My continuing nubeness has me stuck.