I bought the SL5000D (developer edition of the Zaurus) but I haven't managed to get the ROM upgrade to work yet. So far this thing's been a waste of time & money.

I have been lucky enough to not have any upgrade problems with 5000d or 5500, but I have certainly seen reports of same on the sourceforge Zaurus lists and zauruszone forums. Perhaps some of these were yours? Now, ROM updates for the "D" are lagging a bit behind the 5500 updates, causing some to question whether Sharp will continue to support the D adequately.

I sold my 5000d on eBay and got a 5500 not on faith (not my style) but because it is a gem in some respects and I want it to succeed -- it nicely meets a few requirements I had for a sunlight-capable, CF-enabled handheld that can serve as an ocean-going remote control for the Empeg and as an in-car rally computer that can operate in Alcan bright-white conditions (with backlight for night driving).

It will probably do those things for me come what may, but whether it is a commercial success remains to be seen, IMO (see my follow-up post on Zauruszone under "Why the Z will remain a niche product")

Sharp has a lot of work to do. Will they do it? I don't know. It is too bad that thing has been just a time suck for you. FWIW, Sharp does say that a 2.3x ROM for the D model is on the way, and if you perhaps haven't seen the zauruszone/sourceforge troubleshooting posts, maybe there's some joy there for you. Interested to hear if you have any luck. PM me if I can be of any help.