Lady Patch:
I'm tempted to buy one of these but are they any good? Would I be better off and a lot cheaper using a RJ45 cable??
Any advice would be appreciated
Depends on your setup - if it is practical to use a cable, then use a cable - its likely to be more reliable and a fair bit cheaper.
However if your modem is in a different room or upstairs/downstairs then the MS adaptor works well and just plugs into the usb port at the back of the xbox (no seperate power lead needed)