All Apple products.
The apple purchase I regret is the Magic Trackpad. Causes aches in my wrist and just not ergonomically practical for real use.
That's interesting, i've just switched to using one and haven't noticed any discomfort, yet.
Are you laying your wrist flat when using it? I could see maintaining a fully pronated posture leading to wrist aches over time. I try and keep my hand as neutral as possible when using it, in realist i'd estimate my wrist angle off the desk to be ~45deg, then I use my middle and ring fingers on the pad.