chapin4life

I got my security camaras a few days ago in a bargain hunt but I need to get a a DVR pci card so I can record my question is, is there a big difference between expensive DVR pci cards and the ones they sell in ebay? since I found some for $3 bucks on ebay but I dont know if they work as well as the ones they sell in tigerdirect for about $70 bucks thanks in advance for the help