It's possible to type a lot faster on Dvorak, but learning a new keyboard layout of course has its issues. If you have a cheap keyboard, though, rearranging the keys won't be hard. However, if you absolutely have to type a lot, it might be a bit inconvenient. It took me about a week or two to get used to Dvorak (using both Dvorak and QWERTY) such that I could do anything useful, and having used it for several months my typing speed isn't much short of what I can achieve using QWERTY, though I've never gone through any actual typing training.