hi!
I used to run Cacko too, and i moved to pdaxrom a faw monthes ago. I'm just a basic user, so my experience may not be the most infornaticve one but it's an interesting point of view.
1° 1. What would you gain in moving to the X11 ROM besides the coolness factor ?
* Some interesting apps (Abiword is my favorite one). In my opinion, pdaxrom makes your Zaurus kind of a mini laptop as you can use on it any application if you know how to cross compile this application.
* More tweaking. Lots of apps are customisable (fvwm is a gooooooooooood exemple).
* More headache as if you want an application not available on the official feed, google or ZSI will 4 times on 5 lead you to an incompatible application. Depending on your experience skill, help is often needed...
2. Will I need to reinstall and reconfigure again all my apps and config files after the X11 flash (GAIM, Kismet, wlan, ethernet and bluetooth setups) ?
* I think so. Lots of things are different under pdaxrom. Yet, maybe backing up you config files (for GAIM and Kismet) will work, i don't know. But for network settings, i'm quite sure you will have to set averithing up once more.
I hope this helped you.
Cheers.