I too have been considering APRS. I've been running with GPS and moving map (both in the GPS and on computer) for years, just don't have an HT handy for doing APRS. If you have some gear you want to get rid of ... or maybe I'll finally sacrifice and modify the RS 202.
I'm thinking of getting a Yaesu 8900 quad-band, not that I need the other two bands, but the price difference between the 8800 and 8900 isn't worth not getting it. Then I could mount the head just in front of the altimeter pod. Right now my Icom is mounted the same place that Green1 has his Kenwood (blue display). Problem with that is that I have to disconnect power and remove it to open the hood (both are quick releases, but still), since I haven't had a chance to properly wire it in yet (it connects to the rear cig lighter outlet at the moment).
While I have my advanced licence, I haven't gotten any HT transmitters. I do like the 706 tho. With interests in search and rescue flying, event communcations, and computers, my budget doesn't need more temptations.

73s