Quiet easy to learn
I recently fractured my wrist mountain biking and was unable to use my left hand for typing. It is incredible how the muscle memory for both hands, and the entire keyboard is really in each hand independant of the other. Highly recommend. May even use from time to time when eating or holding things with the other hand now that I have my cast off.
Cheers!
brian
brian sully about Mirror-QWERTY: One-Hand Typing