I really like Dvorak. I don't type much faster, but typing requires much less effort. If you know someone who types Dvorak, take a look at the wear patterns on their keyboard. It's pretty much the home row. Contrast that to qwerty, where the top row (especially the E key) gets an inordinate amount of wear.
It does take a minute or two to initially set it up. Here's an old listing of ways to do it on a wide range of operating systems - https://kb.iu.edu/d/aepk And I would recommend setting up a keyboard shortcut to switch between them.
Once you have it set-up, including a keyboard shortcut, switching your keyboard is just a shortcut away.
I only type in Dvorak, so I can't speak to the ease of a single typist switching back and forth. I have pair programmed quite a bit with Qwerty typists and other than occasionally switching keyboards and momentarily forgetting to switch it, it has never been a problem.