Rockband 3 Midi-Pro adapter (Wii)

I'm a music teacher and this was my first experience with a musical game. I've been waiting for a device like this that allow us to connect a real instrument, in my case, a MIDI keyboard.PROs:- it's really plug 'n play, even if my keyboard is not listed as compatible.CONs:- for this price it should include a MIDI cable;- no manual so as a first time player I had to guess what to connect and turn on first, what buttons to press; that I needed the Wii Remote to start, and so on;- does not allow expression, because does not use a very important part of MIDI specification (since 80's), Key Velocity aka Touch-sensitivity.BOTTOM LINE:I was expecting not only to play a musical game, but to play it "musically". Unfortunately it does not work like that.