You can buy Western Digital BEVS or some such and then flash them to work. The method is probably frowned upon here, but if you google it then there will be guides telling you which models work and how to do it.
Or use Alpherahs method and it will work right away.
has any one tried this?
Yes, it works. Also, MS will not ban you for using either an official or unofficial drive. Sure, it's technically against the ToU but they don't ban for it.
silly question is the 4gb flash drive removable? so you swap the 4gb drive with another?
ah ok, so the drive bay on the 4gb is empty? I thought you would take the 4gb out and fit a 250gb..
You can get the 250gb slin hard drives online for 69.95