I really took my time and measured every angle this time around. A few years ago I purchased a used Panasonic CF-01, an early comer in this world we call TPC. Tired of the tiny screens and limited usability of the PDA, I knew back then that I wanted something running full windows in a small super-portable. The CF-01 runs Win 95 with pen services and is really a cool little machine --for 1998 that is. I've been waiting and watching since the fall of 2001 for the "right", in my eyes, machine to come along.
The Fujitsu 5010d does it all for me! Price + features finally came together and I could wait no longer. (the CF-01 was almost 3K when it came out!) I too already had Notebook(s) so I knew the slate was for me. Also like you I was looking almost exclusively at Toshiba and Fujitsu. I've either owned or used just about every laptop/notebook made since Radio Shack's Model 100 (wow, showing my age with that one!) and am convinced that Tosh and Fuji products are superior. Later I did consider the Motion 1300 as a contender due to the "slate" factor.
When you narrow the field to two or three as you apparently have, my only suggestion is to try to see each one. Hold it, play with it, see how it feels! I would only recommend a convertible if the machine is to be your everything.
You can run any of your existing software and a lot more!
Good luck and be sure to let us know what, when and why you've made the decision.