Comp USA has a price match policy but it sucks!
For example, here in NYC, one of, if not the biggest electronic stores is J&R Music. EVERYONE in NYC uses them to compare prices as they are often the cheapest.
However, Comp USA claims J&R is not a competitor. There is a huge electronic store across the street from a CompUSA here called Data Vision and again, Comp USA says they are not a competitor.
Bottom line is, don't count on CompUSA to price match anything until they give you the money!