I certainly agree with the concept of using lower-power amps for surround and ceiling (‘S&C’) speakers. Within the last couple years, for S&C speakers I’ve used 150W-(all into 8) channels of Butler TDB 5150s, 100W channels of an Outlaw 7100, and 80W channels of two Emotiva A700s. I have found that ceiling speakers require more power than surrounds–at least the way I have them level-set–and the Emotivas do just finely. I’ve never noticed ANY amp clipping driving S&C speakers, and I’ve never noticed ANY sound-quality differences among the MANY amps I’ve used for S&C speakers over the decades. FWIW, I also don’t feel the need to ‘match’ the SQ of S&C speakers to that of the main speakers, and I’m quite pleased with the overall performance of my many B6s, some purchased (new) for as little as $200 per pair.
Currently I’m using BHK 300 monoamps for main-left and -right (and LOVING them!) driving the 86dB-insensitive Quad '2905s and two Emotiva A700s (totaling 14 channels, some not used) driving the 10 S&C speakers, those being 87dB-insensitive ELAC B6s.
FWIW, I also use MUCH-less-expensive IC and speakercable for S&C channels.
Visible here is the pair of front-ceiling speakers.