I recently bought a US Robotics wireless access point and PCMCIA card from PC World and spent a day trying to set it up. After banging my head against the wall and kicking the cat once or twice I took it back, they checked it, said it was faulty and replaced it like for like. Got home and same again, took it back and exchanged it for D Link equipment. Up and running within half an hour. I later found out that PC World re-wrap returned goods in cellophane and put them back on the shelf.
The wireless set up seems to work OK but forget the advertised range. If you're in the same room it's fine, OK in the room immediately next to it or immediately above but more than one wall between you and the access point/router then it gets very temperamental.