I'm always impressed by people who change their own tires, and I know it's not that hard with a second set of rims, but I've also come to appreciate that Discount Tire will change them (again, assuming a second set of rims) for free each season. And since this season's changeover was also the point at which it was time for new summer tires, I was especially pleased today when they swapped the initial set I'd bought (which was OK and what they'd had in stock) for my choice tires (with better gas mileage and which I'd been happy with before), for no extra labor and only the difference in price, after about 3 weeks on the old ones.