I have clear bras on 3 of my 4 Vettes and on my Camaro. Three of them are Scotchcal one is an imitator. All the Scotchcal installations have had no problems with yellowing or peeling. The one I have that's a Scotchcal competitor has some problems with peeling.
If you buy the best clear bra, one made of 3M Scotchcal Paint Protective Film, and it's applied by a factory-trained installer, it will last about ten years on a car that's garaged will not yellow and won't peal.
If you buy one of the other PPF's, several of which are significantly less expensive, be prepared for a less-durable product which might yellow.
In the beginning, back in the early-'00s, there were only a few vendors who sold/installed clear bras. Nowadays there are many but a fair percentage of them sell crappy material and are either poorly trained and/or lack experience and/or try to get the job done in a hurry. If you deal with an installer like that, expect the bra to peel in a few years.
You didn't say how extensive a PPF installation you were going to purchase, but typically, people do the nose, the front of the hood, fender sections behind each tire, the mirrors and, maybe the rocker panels.
I'd say, if that's what you're going to do, 500 bucks is pretty cheap. Make sure of your materials and your installer's training/experience.
