This tablet is an undiscovered hero for artists, none of the companies making these seem to be marketing them correctly but if you scour the Internet forums like I have you will find that you can load Wacom drivers onto them and have full pressure sensitivity (512 levels I think) in all your favourite drawing programs and some smart folk have even developed a touch-screen hot key shortcut menu which has revolutionised my process.
The tablet is about £700 on Amazon and they were first class as usual with delivery etc. I won't bore you with the details you can find elsewhere but I WILL show you exactly where to go for the pressure sensitivity drivers and hot key software. It took me days sifting through forum posts etc to figure this out. Unfortunately it is not set up "artist friendly" out of the box.
First off go to http://support.asus.com/download.aspx?SLanguage=en&p=28&s=3&m=Eee+Slate+B121&os=&hashedid=Sr9xAv0Y2ZyvhqXw
After that follow instructions on the following link for the touch panel thing and the custom pressure levels.
I hope this helps people to have less of a headache with this than I did. I cannot recommend this tablet enough for professional artists. If you are considering a Wacom Cintiq, then this will almost certainly be a fine alternative.