I got an idea. Why don't you check your attitude. You put this post on here, complaining about how other have not put information for you about whether your decision to paint your bumper is wise. Seriously? Back away from the Espresso machine, take a deep breath, and realize that it isn't OUR responsibility to do your homework, and stop complaining about it here.
Now that I have gotten that off my chest, I know 2 people who have had this done, and it looks amazing. Both of their vehicles are 2 years old, and to my knowledge, neither has had an issue. Their cars are approximately 2 years old. I was told by 2 high end shops that this was doable on my 08 4.8, but never did it. The key is making sure the surface is prepped right.
Now, please feel free to go back to complaining....