I find the Mac version creates less strain. It does harm muscle memory, though, if you have to switch between the two often. On my Mac layout I basically never

I find the Mac version creates less strain. It does harm muscle memory, though, if you have to switch between the two often. On my Mac layout I basically never touch lower-left ctrl, just cmd (which is faster and requires less movement and stretching to strike than ctrl does) and CAPS LOCK, which I've mapped to ctrl. Pressing bottom-left-ctrl makes me rotate my wrist and stretch my pinkie down—I don't have RSI in my left wrist, but I can feel the tension that motion creates. Cmd, I just shift my thumb over an inch or so, no wrist rotation, everything stays more relaxed. CAPS LOCK, pinkie just moves a few mm left, other fingers can stay where they are unless needed for something else.