I've owned Monarchy SM-70 Pro monoblocks, a Rawson First Watt F4 clone, and now an Audiosector Patek. All are great in different ways. The Monarchys were the most tube-like, ran very hot, and were too noisy into my Zu Druids. The Rawson ran *extremely* hot, was a little more neutral than the Monarchys, was dead quiet, but ran out of gas when I turned it up. The Patek is very neutral, also dead quiet, has plenty of power, and never even gets warm.
All were run with tube preamps (Wright WLA12A, Jolida Music Envoy, now Consonance Cyber 222) and right now I'm pretty happy with the 6SN7 preamp and gainclone combo.
David