Just get the amp that sounds the best with your speakers. The only limiting factor would be if you needed to hide the amp in an enclosure.You'd have no problems running class A amps at hundreds of watts day and night in the living room?
Unfortunately no dealers out there with Focal Stella Evo's on demo with several different amplifiers to audition.
Let alone my considerations: Gryphon Mephisto, Luxman M-900u mono, and D'Agostino Progression mono.
P.S. I may want to have some enclosure around the amps, but easy enough to add some active ventilation with quiet fans.