I agree that a 331 (might) sound better than a 27 (certainly not worse). However I'm of the opinion (along with many others, I might add, just search the threads) that a 27.5 will sound better than either one of them, in a number of important areas: soundstage, midrange openness, bass articulation, headroom, high end smoothness, and not dark sounding like the new stuff.
In fact, the only recent amps by Mark Levinson that equal or exceed the performance of their "Golden Age" amplifiers (the 20.5, 20.6, 23.5, 27.5) are the 33 (no longer in production) and the 33H -- primarily because of their amazing "power regenerator" type power supplies (not in the 300 or 400 series) and even better (than Teflon) printed circuit boards and newer component devices.
If you're searching to buy brand new SS amps, I'd look elsewhere if I were you. Sadly, because I've loved Levinson equipment for a long time. But today, there are much better choices in that price range. Pass, Lamm, Rowland, Boulder, darTZeel, Goldmund, FM Acoustics, etc., if you really want to spend that kind of money and buy new stuff.
.
