I was fairly proficient with QWERTY for a long time (about 75wpm) until I began to experience pain in my right hand pinky. I finally made the switch to the Dvorak layout. It was frustrating at first; it would take me close to a minute just to type my own name!
I stuck with it, though, and eventually I got much better. Today I’m up to 90wpm cruising speed, and I can reach over 100wpm if I really punch it.