We sell AC Delco batteries for the most part, and after they stopped having some of there batteries made in Korea the warranty problem went away. Most of our customer like the free replacement period and not the prorate. We had lots of problems with Interstate and warranty but that may have been the driver not the company but they still lost our business. I had to eat several batteries out of our own rental cars because the driver never had a replacement on the truck and I wouldn't wait for him to bring one later in the week.