I have had RSI off an on over the past 2 decades. There are only two types of 'primary' keyboards on which I have no issues: my model M, and a curved layout keyboard (using a microsoft 2000 keyboard these days). I think they work in different ways. The curved layout avoids straining my wrists altogether, while the model M changes the 'quality' of the strain to something less harmful. Of the two the model M is definitely the nicest to type on. Anything you type on it feels important. It is too loud though, so I don't use it anymore. Also, my typing accuracy is much higher on the curved layout of the microsoft 2000.