to be honest i've never had any reason to send items back to them yet for warranty claims but in the main i've never had any luck with warranty's with any company, its always our fault as we fitted it wrong or we didn't flush out the system properly etc.

Thermostats seem to be the biggest problem, now i just cut the middle out to test cars for overheating and when they seem fine fit new thermostats and then go from there.

Another thing i find, when you ring up the manuafacturer of any part to complain your always the 1st person to ever have a problem with said item.