My primary target was to have a dual boot system, so I first installed Windows XP (a properly reduced version) on the 4GB internal disk (sda) then I proceeded with EEEBuntu installation on the 16GB internal disc (sdb).
Usb drive preparation:
I did choose the easy way to prepare my USB drive to boot with EEEBuntu. I downloaded and installed Unetbootin, Windows version, and used it to easily prepare the boot drive from the already downloaded ISO file. (this is the fourth boot-from-usb tool I install since I bought the EEEPC)
EEEBuntu boot and Installation:
After EEEBuntu boot I launched the installation program. At first I didn't see disk sdb as available for install, after a while I realized that the disk has to be flagged as "bootable" to be visible from install program. I used GParted to set the boot flag on disk sdb then I continued with installation. I did choose default options for installation and everything went fine. After installing I entered in BIOS set-up and selected disk sdb as first boot device in order to boot into EEEBuntu by default.
First impression EEBuntu gave me was the feeling of working with a full system, with a graphical interface well suited to the EEEPC small screen. I never felt using a limited interface like the original Xandros "easy mode". I haven't installed any application yet, apart from FBReader, so I haven't appreciated yet EEEBuntu repositories completeness, one the main advantages in passing to Ubuntu.
The main disadvantage of EEEBuntu is loading time: it takes almost two minutes to have the computer ready (Xandros was quite faster in it). One more minute of wait time is not very important if used during a train trip which lasts 30-45 minutes (during lucky days).