Thanks for your comments - bought a Wacom. By the time I learned my way around the pain went away and I'm back to the mouse. Tried the stylus again after my arm stopped aching and was able to use it but I don't sketch with Flexi, as it is not actually a drawing program per se. For me it is more cumbersome than the mouse. I don't design in the field, but if I did, a stylus on an I-Pad would probably work well. Other than that a quick hand drawing with pen and notepad work just as well and are faster. Old School.
Thanks again