I just installed these wind diffusers and although I did not get 15% off I will still endorse them and say that they do work. There are times where there is wind buffeting but generally it solves the problem and you don't have to open both windows in order to drive with an open window. Installation was simple as you just had to realize where the screws would come through to decide which of the adapters to use but prying off the inside piece was easy but just be careful of the hook on the bottom.