[Some_Guy]

I've been using a Logitech that must be similar to your #2 choice (don't know the exact model) for over a year now and have never experienced any thunb/finger discomfort.

I don't always have a surface to use a mouse (we move often) so the wireless trackball works best for me.

As far as the difference of using your fingers vs thumb, if people are not reporting joint probelms with either then I imagine it just depends on wich one you are used to as far as ease of use.

GOod luck!

JP