I had the same experience as Omar Shahine and Anthony Murawski - I brought them a flat that had a puncture and a leak, which they fixed it free of charge, and pumped up my spare to boot. I guess the business model works, because I'll definitely go back the next time I need to buy tires.
Fantastic. I bought my tires there, and had a flat (nail puncture) two years later. They replaced it for free. I was pulling out my wallet when they said it was free.