I used to, but over the last several years I've been buying based on price, tread design, and customer ratings and it seems to be working out well. I buy tires that are on the lower end of the pricing scale, but not necessarily the least expensive. Over the last 5 or 6 years I think I've had one or two tires go bad, but since I always buy my tires at Discount Tire, they always replace them prorated. I've always gotten the rated mileage or better, even with the least expensive tires. I know some people swear by certain brands, but I think a lot of what you're paying for with those tires is the name. I don't necessarily think they're any better than the "cheap" tires...