I use them and love them.

I was experiencing finger and wrist pain from typing and switched to a mechanical keyboard, which seems to have stopped the pain. Note that I also went to a tenkeyless layout in order to prevent a lot of motion when I move my right hand to use the mouse.

You'll want to do some research into switches, as not all mechanical keyboards are alike. The most popular variants are probably Cherry MX blues and browns. I prefer the clicky feel of the blues, but they are really loud.