it would seem that all the NAC warrantys are a waste of time. Stamped or not as you still need invoices to proove which they also dont give you. I never even asked for a warranty told one came with the car but yet i have been charged 1,270 for in one year i havent had the service history stamped therefore its void anyway. Yet its two years free warranty oh my god i cannot believe carcraft have got away with this there are thousands of people complaining. Seek professional advise they are conning people on a daily basis