Sometimes they will do exactly 10% even if the actual matched price would be higher. I called to get a price match for a Retina iMac when Best Buy had a $200 off sale this Summer. The discount from Apple ended up at -$230 (10% off Apple's store price rather than a match of BB). Plus I saved another $23 because the sales tax rate was lower, and it was a 10 minute drive vs. 45 minutes to the Best Buy that had one in stock.