I have never purchased anything there. However, when buying a computer online make sure you know what their return policy is if something is wrong. It can be from 30 days to 3 or more years. Some places offer a standard 1 year or more guarantee on the system.
I have seen a lot of problems posted by people who purchase a computer with a PC Chips motherboard, so stay away from that. Other problems occur when purchasing integrated systems that have the VGA (Video Card) integrated into the motherboard. If you want to play games, do not go for this option.
Be prepared to spend enough money to get quality parts. Don't expect a $600.00 computer to run like a $2,000.00 one.