A bit late to the party but I bought an MCU & XT off ebay at a silly price considering what they were new.
My cat managed to knock something off a shelf that landed smack on top of one of the faders so it wouldn't calibrate properly.
Took it to bits myself and sorted out the fishing twine mess that the fader had become. Fiddly, in fact, very fiddly but fixable. Now working fine again. The faders are the weak point but they clean up okay and there is a great site out there somewhere for fixing and cleaning faders including the touch sensitive strip bit.
I wouldn't be without mine.