Have bought two different game systems from here i...

Have bought two different game systems from here in the last week. It was a gift for my father. First a x-box 360 and even though it says 100% GARENTEED it didn't read ANY discs and we had plenty . So go to take it back and I didn't have my receipt thinking the unique box would say it's there's since it's the only business I've ever seen use those. And they wouldn't take it so long story short I buy a PS3 instead and it doesn't read any discs either!!!!! Stop saying it's 100% GARENTEED when it's NOT!