I have direct experience with this one! First off, be very wary of the bulbs you are purchasing. The ones that I installed were very high quality APC LED bulbs, specifically manufactured for Chevrolets (they were around $20.00 for two bulbs and were the correct part number, I believe 3157A?). Suffice to say, they did work, but then blew all of my rear light fuses, as well as my turn signals. I actually didn't care for the way they looked, due to the lack of relection inside the light housing. LED'S *DO NOT* refract/reflect light to the sides, therefore, you have only a straight-forward concentration of light. It looked okay, but nothing special, and without a doubt, not nearly as bright as the stock bulbs (which reflect on all sides), which are reflected by way of the reflective chrome panels inside the light housing. I suppose this mod is one that it personal preference, as long as you find the correct bulbs.
Cheers,
Justyn~