If and when Future Shop gives you a hard time, point to their lowest price sign.
One excuse they like to give is that since Dell does not have a retail store, they cannot price match them. This of course is pure BS since nowhere in their lowest price guarrantee is that mentioned.
If they do give you a hard time, call Future Shop's head office and file a complaint. If it is a valid price match they will usually call the store and arrange for you to get the price match. The same goes with Best Buy, Staples etc.