I tried dvorak for a couple of days before switching to colemak, I managed up to 30 or so WPM with dvorak. Before I switched I was able to type at about 80 WPM just by hunting and pecking with three fingers. I'm still able to hunt and peck qwerty at about 60 WPM, so that's good enough if I'm forced to type on any other keyboard than my own. I'm able to manage up to about 100 WPM now, so that quite an improvement, altough you're not very likely to use it at even remotely that speed very often.

I only used 10fastfingers to train, nothing more nothing less. It seemed to have done the trick for me, although typing in English is remarkebly slower than typing in my mother tongue.