MCU is a nice controller, especially with an XT or two to up the channel count. Very nice for fader and transport controls. Programmable hot key buttons nice also and some other nice features.
However, it's a bit long in the tooth at this point, yet still very pricey, particularly with XTs. I have and MCU and three XTs and will continue to use them on my main machine (gotten very comfortable with real faders, m/s buttons, scroll wheel, etc.). Also, the plugin implementation is decent, but not programmable (AFAIK) and therefore I find myself just mousing plugin controls most of the time instead of trying to find the control I'm looking for on the scribble strip!
As I posted in another thread, I just ordered a new machine and Planar Helium touchscreen; the 27" touchscreen is much less than the MCU, never mind adding and XT or three. I'll report back once everything is in place.