This is a great question, thanks for asking it. We're planning to buy a freezer soon and were trying to decide where to buy it. We have a bunch of credit card points saved up that can be redeemed for a store gift card, so I was going to go with Sears since they usually have good prices and the Kenmore we used to have was excellent.
Even without the discount, the free delivery is a good buy. We can always use a 10% off coupon for something else in the store.
Home Depot and Lowes accepting each others' coupons is a good tip, too: we used that for a grill we bought at Home Depot with points-gift cards, a sale, and a Lowes coupon. We ended up paying a whopping $20 for an awesome gas grill ... because I picked up a rotisserie attachment, lol.
I think I'll get the Lowe's cards and keep an eye out for sales at both Lowes and Sears.