I started using dvorak some years ago.  I have since switched back.  I don't think it helped my speed or my hands, and there were too many other costs which made it not worth while: having to set it up every time you reload your OS or start a VM, or change window managers, etc;  it made the vi editor unusable, and while I mostly use emacs the ubiquity of vi makes it inevitable; using other computers in the lab became difficult, because they are shared with other people who used querty; it sometimes confused some programs and made them unusable; and so on.<p>I don't think there is a long-term gain to be had.  Read 
<a href="http://reason.com/archives/1996/06/01/typing-errors" rel="nofollow">http://reason.com/archives/1996/06/01/typing-errors</a> for an account of the qwerty myth.