I did my 335 with clear bra at purchase. The car now has 21,000 miles and not one chip! The car looks essentially new. I would for sure do a clear bra even if I was in a lease or even driving in town only. Mine is also on a 1/3 up on silver and the line is not that obvious. I do wish that it went higher since I have 2-3 chips on the hood by the windshield.
Also, my side rear view mirrors are done from 1/2 down on the front and I have received a rock chip on the top of the mirror, so I would do the whole mirror front.
I would say at the at the very least you should do your front lights.
2011 E92 M3 - Space Gray, ZCP, Akra Evo System, aFe filter, PC Stage II Tune & more!!!!