Trouble with the 3m (I've experienced on other cars) is that you get white lines where you polish the car. These lines are hard to stop, and get the polish out.
If you have not experienced this 3m before, just look down by the Gt's wheels, there is a small section already treated to stop stone chips thrown up by the wheels.
The other proble I have with 3m, it does not allow you to treat, clean the paintwork, and I've newver been happy with the shine you get against real polished paintwork?
These are small areas you will need to compramise on if you want to protect your car from chips, there is not an ideal answer.
The Bra gives you protection whilst driving and you can take it off for shows and to admire the original paintwork, but it does look a bit naff on, and the name "front bra" who came up with that.
Probably the best compromise is the Bra, you get the best of both
1. Protected pain
2. Still original polished finish