Hi Eddy,
I have a 701, as far as I know the 900 is not yet available in the UK yet. I find it very good within the limitations I would expect for it. It has a small but very clear screen but I would not ever push it as a main PC. I have a dektop and a full spec'ed laptop but the Eee PC is great to put in a bag when I just want to do a bit of work or check my mail.
I have kept the LINUX it was supplied with, although XP drivers are provided. Open Office is very good and probably nearer to Word 2003 than Word 2007 is. I switched away from the simple interface applied out the box to the "Advanced" interface, a standard LINUX desktop.
I have a 3G USB modem that works very easily with the Eee PC to give Internet connectivity when Wi-Fi is not available. I use that together with Virtual Private Networking and Remote Desktop software (rdesktop is installed as standard) and can log into my work desktop PC and run Windows programs on that.
There is a very active and helpful user forum at:
EeeUser.com » Unofficial ASUS Eee PC EeePC 701 Blog Forum Wiki Community
I find it a great little device. If I can help please get in touch.
All the best,
Martyn