I changed from Pass Aleph 2 momoblocks to ARC VTM 200 monos several years ago and I really liked the tube warmth that I gained. And ARC hybrids are not known for having a full clasic tube warm sound. Also, the Aleph 2s were regarded as one of the more warmer sounding SS amps out there.
Count me as fan of ARC and Vandersteen.
BTW I upgraded my ARC coponents to the Ref 5, the Ref 2 phono and the Ref 210s and I am very happy with the combo with 5As.
I also have a Ref110 that I use during the summer, a slight drop off compaired to the 210s IMO mostly in the low bass and low end slam. From what people have written it seems as though a similar difference exists with the Ref 150 and the 250s. I have not heard the KT 100 models but I bet I could live with either.
It is interesting that Richard uses or initially used Ayre with his 7s. But the 7s are a bit less efficient than the 5As and also the 5A carbon IIRC, so the extra power might be nice to have. Ayre would be the first SS amps that I would check out if I were to go that way but I can also see why you are looking into the Aesthetix.