Here's my story -
Once upon a time I had a Ferrari F430 spider. I bought it up in New York with about 1200 miles on it. The dealer had sold it new to the previous customer who had this teflon coating applied for about 1500, and I was told I'd never have to wax the car again. It looked great, no swirl marks and I was pretty impressed.
Then I moved back home to Texas. The car lived through two 100+ summers and spent a fair amount of time outside while I was at work. It was a red car, and I started to notice that after the two summers the clear coat was yellowing! I was told by my trusted auto shop in Texas that 1 - I never should have bought the car with this on it, can't survive the sun without breaking down, and 2- you can't get it off, you have to wetsand the card down pretty far, then reshoot and reclear, which on a Ferrari is about the same as buying a Raptor.
I sold the car.