I upgraded an old
HP tc1100 with a 64GB SSD/Windows 7 and currently use that to read PDFs (textbooks mainly), web browse and sketch on; 10.4" active digitizer. I really wish HP would revive this form factor with current hardware. Win 7 runs rings around the XP install that the system came with. With wifi/bluetooth off and undervolting I can get about 3.5 hours out of a fresh battery. If I remember correctly you can hotswap batteries, although I haven't tried it yet. The tablets weights about 3.1lbs without the keyboard; a hell of a lot less than textbooks.