I too have been very pleased with the iGo XTBT01. Once synced, it remains so (although the first character you type after it has fallen asleep takes a couple of seconds to register).
Small size when folded, nice zippered leather case included, reasonable typing speed.
One nit on the keyboard: If you're a command line user, the up-arrow key is where the slash should be - so you'll tend to regress commands when typing paths. :-)
One nit on using any Bluetooth keyboard with the N800: When in "off-line mode" (to save power when not using WiFi), Bluetooth is also "off-line" and the keyboard doesn't work. I'd prefer to control Bluetooth and WiFi radios separately.
But those are small nits compared to the convenience of a good portable keyboard. Definitely recommended.
I use the Apple Bluetooth. There are MINOR connection issues. All I do is disconnect the keyboard via the quick menu at the top of the screen. Then it reconnects in seconds. Otherwise it is excellent.
