Yes I have, and I have experimented with different vinyls/films and they all end up looking like trash once you project light through them.
I may be using the wrong film, but I was using a high quality Oracal vinyl and it just never looked right.
I wanted to achieve a light smoke just to tone them down a bit, but it looks like the only way to do may be painting with a spray - and that is too risky IMO. So unless I come across a different vinyl, I just rock them clear.
In this photo they stand out more, due to the clouds, the vinyl has a full matte look with no sun - and has a satin look with sunlight. Thus the headlights being a reflective surface stand out way more on a cloudy day.