I switched to colemak a year ago. Best thing I've ever done. The first month was REALLY hard. But I got over the slump and now I'm very grateful I did it. Typing is so much more natural feeling now. All the stretching in qwerty is not good for you.
I was starting to get signs of RSI before I made the switch. But now almost no pain at all. I switched to an ergodox at the same time, so I can't tell you if the keyboard or the layout made the difference, but I think they both are a factor.
The one thing that really helped me make the switch was changing the layout on my phone's keyboard as well.
The one thing that really helped me make the switch was changing the layout on my phone's keyboard as well.