I prefer ss amps with my M3 Sapphires. I use tubes up the chain. I have First Watt F5 and F6, also Devialet, Hegel H20 and AudioSector Patek. All are outstanding, with subtly different presentations. I have used tube amps as well, they do sweeten up the sound but give up bass control... LTA. Carver and ARC work well, with better bass control among tube amps. The speakers are tremendous at realistic bass reproduction, and coming from other speakers, tube amps driving the M3S may well please many listeners with the bass quality, but for the best sound, I feel top flight ss is preferable, with tubes further up the chain. Depends on what you prioritize.
Cheers.