I'm not sure what ADB backup does. As far as I know the mounted partition images are differently named to various backup tutorials, so I get the feeling ADB backup just simply copies the user data and not much else. I recommend doing the backup I mentioned as well, it'll at least capture a copy of the boot partition, which if the device doesn't have that you'll probably need to revert to using live suite or some other firmware utility to restore it. Getting the firmware for that is another story, read a fair amount of posts here and other places on the net that don't sound fun.
I personally still can't get superuser to behave for using su on the terminal/term.apk (I want to remove useless "system" apps and make sure the device isn't talking back to anyone, i.e. google), but I'll keep tinkering.
My main aim for getting one of these tablets was to boot other firmware from the SD slot, but it looks as if the u-boot process is locked to internal NAND. So might have to modify it by adding "fatload mmc" to the script.