jbiird317,
I have not heard anyone with 3M clear bra fading. Once the clear bra is on, it's like part of the paint so the dirt won't get in it. Unless of course, you take it off and reinstall it. But why would you?
Danstona,
The reason people suggest getting it done early as possible because that's when the paint is fresh. In another word, swirl free and rock chips free. If you have driven your car for a while and washed it couple of times, chances are you'll have swirls or minor rock chips. So, once the clear bra is installed, you won't be able to detail those swirls off and the repair those rock chips. Unless you want to blow $800 to take the clear bra off and repair those damages. For example, I had my parent's pathfinder clear bra installed the next day I drove it off the dealer. In between, it was just parking in the garage to avoid any damages.
I would highly recommend this if anyone intend to keep the car clean and for a long time. It would definetly boost the resale value. That's of course, if you can afford the cost because it is quite pricy. But the result is well worth it.