I kept mine pretty close to a standard qwerty - the only customizations are where I put the "\|", backspace, dash and a few other keys, along with what to do with all the thumb keys. Even with these relatively minor changes, it still took me about a week to recover my WPM, and I had to use their touch typing software to practice for an hour or two. Making only a few changes also makes it seamless to switch to laptop keyboards, etc.