Hi David72,
Wholelife warranty? better ask for a warranty certificate in black n white. Better check if there is any other conditions such as have to come in half yearly for maintenance etc. Any other misc expenses? If 1.5K for whole life warranty is definitely worth it.
Good to beware also of bad car detailers that might say : lifetime warranty or 5 years, whichever comes first. In this case, we are looking at a 5 years warranty. Life time can also be subjected to the life time of the glass coating.
Check and let us know. Cheers!