I have a Kinesis Advantage 2. It's not at all about performance, in fact I still type slower with it. The entire point is that I have pretty broad shoulders and so typing on a normal keyboard, my hands are at a very awkward "up-and-out" angle. With the Advantage 2, my hands are straight with the wrist, pointed inwards and slightly down, and need to move very little. It's pretty relaxing.
(Though whoever decided that alt-tab should require a crazy hand-spread gesture with the outside fingers spread wide, needs to have their head checked. And the function keys are an affront against all that is good in the world.)
(Though whoever decided that alt-tab should require a crazy hand-spread gesture with the outside fingers spread wide, needs to have their head checked. And the function keys are an affront against all that is good in the world.)