Coincidently, one of my more recent experiences with Quads (2905s) was listening to them in a store with the MV 60 and CT6. Did you hear them in a store in Baltimore by chance? At the time I already owned the CT6 with a pair of Music Reference RM 10 amps. At the time I was also considering moving to Quads since the Music Reference amps are voiced with Quads and I was told a very good match. Well not only did I pick-up a pair of 63s shortly thereafter which sounded quite good with the Music Reference amps, but I then picked-up a pair of CJ Premier 12s.
To answer your last question, IMO the MV 60 and CT 6 are a very good match, at least with the 2905s, and I would assume with the 988s as well. However, to answer your original post, I can highly recommend the Premier 12 mono blocks with the CT6 and Quads. In my more than 40 years in this hobby, it is one of the most musical and satisfying combinations that I have ever owned.