In October 2005 I brought my Sony laptop to them for service, and it came back with all the case screws in the wrong places, causing physical damage to the case and a big loose gap in the front edge. Then, a year later, they again returned my laptop to me with incorrect screws, and with a wad of tape wedged between the keyboard and the cooling fan!
That started a saga, still ongoing, with more missing screws, a heat-related video problem, a damaged hinge cover, missing protective covers for the LCD's screws, and four months of broken promises, abysmal customer disservice, and lack of returned calls on all levels from the local store's tech services manager, operations manager, and GM up to the corporate manager of customer service and chief of escalation.
I've posted my story on my blog at http://www.onefromtheroad.com/index.php?cat=11 (posts are in reverse order, since it's a blog!)
Please help me spread my story, and hold CompUSA responsible for mistreating their customers like this!
P.S.-For futher episodes of CompUSA being involved in grossly mishandling repairs, see http://forums.macrumors.com/showthread.php?t=2800