I have a clear bra on my Pana and have had them installed on every car I've owned since 2004...a lot of cars now that I think about it. Anyway, I have had no problems with them as we'll as peace of mind from front end damage cause by bugs and road debris. Clear bras are a must in my opinion, unless you plan on repainting your bumper every 2 years or so.
2011 Panamera 4S...GT Silver / Espresso
2012 Mini CooperS
2008 135i Convertible - Sparkling Graphite Metallic
Prior BMWs: `05 645CiC; `07 650i; `08 M6 convertible; `11 750ix MSport