I can't say if either of those amps would make a sonic difference, because I don't know how loud you listen to your speakers. They certainly might, though.
The MX-2000 is a beautiful amp. The wood sides are a very nice touch. Here is a nice
internal photo of one if you haven't seen one already. It is Class A, though, so I'll bet that it'll run hot and probably suck some electricity.
The MX-1 is much more mundane looking, IMO. It's also Class A (I think), but is supposed to be more efficient.
I'd have to research it more to know which one that I'd prefer. Hands down, the MX-2000 wins in the looks department. I don't know which would be a better performer, though.
Adam