I agree - it seems low, especially for a performance car.
BMW's insurance-backed warranty (details at http://www.bmw.co.uk/bmwuk/owner/services/insured_warranty/0,,1312___dht-aHR0cDovL3d3dy5iYXllcmlzY2hlYm13Lm5ld2RvbG4ubmV0,00.html) seems to be similar in cover -- both in terms of claim...