I bought an xp3 canister filter from petsmart. I was going to order it from the web, but it was backordered. The local store had it for a higher price, but they matched the internet price. They needed a print-out to show the price. It would have been a little cheaper on the website (no tax, plus a web discount, etc.) but I still saved a bunch. Cost $104, instead of $179!
Yeah PetSmart will match any of their online prices, you just have to show it to them. I always check the prices online before I go to the store for anything.