After a month of using one of these...
...I'm really happy with it. I swore I'd never buy another Windows machine but so far, this little machine seems to be pretty stable and does what i need when I'm out and about. I'm spending up to 8 hrs a day using the built-in HSDPA and it's just about glitch free.
Real world battery life with HDSPA on and the screen a couple of notches below full brightness is around 3.5 hrs and it's about the same with wi-fi on and HSDPA off. Upping the RAM to 2Gb cost me £23 and made a big difference when switching between 3 or 4 apps but the machine ran perfectly well with 1Gb.
I'm feeling pretty guilty about leaving my 17" Macbook Pro at home every day but for coffee shop and motorway services us, the 4213 is a winner.