The Art Audio Carissa is a great amp and its power rating is very conservative. It will drive the VSM very well and will suffice for the TSM if you don't listen to extremely dynamic or head-banging music. Bobby, last time I checked, doesn't prefer Art Audio with his gear. I, on the other hand, love Art Audio with my Merlins. Bobby has a strong personal taste towards lush and warm electronics (e.g AA Capitole, Joule) and accessories (e.g Cardas) to mate with his speakers.
How many watts are you pushing your Merlins with?
I'm thinking of going from 60 watt mono's(ASL) to a 16 watt stereo(Art Audio). I don't play loud music and the space will be 16 x 11 x 10. Will this be a mistake?