Installed the rear window louver by Willpak this past weekend. The installation was easy, but tedious and time consuming. You will need two people, and patience and a few dry runs on fitting the louver before you take the tape off. I purchased the louver from Willpak simply because I wanted one and Willpak seems to be the only game in town for the 2011-2014 Dodge Charger. Instructions were detailed and accurate. Fit and finish is acceptable, but not by much. If Willpak had some competition they might have made a better product. It's also possible that Willpak found a louver that was already in their inventory that would work. Hense the reason why the fit isn't as good as it could be. While dry fitting the louver, I had to move the louver far enough up to allow the trunk to open, the louver sits a little too high and shows noticeably while only allowing a 16th of an inch for the trunk to open. The Louvers also block out the rear window viewing area more than I think should be necessary. Again, maybe this product was meant for a different car, different slope and just retasked for the Dodge Charger. For the amount I paid, I think I could have gotten a better product, better fit and finish and hinged. If I had to do it again, knowing what I know now, I would have looked into a custom set. I'm not going to remove them but try and tweak things a bit. Driving with them for a few days, I've gotten used to them. The rear visibility is hindered, but driving trucks my whole life, this isn't really an issue as I'm used to looking in multiple mirrors to see what's going on behind me. The fins do vibrate slightly at speed above 60mph, they're not bouncing off the glass but you do see some movement. The two main issues with fitment is that 1: about a 1/4" too tall and/or not enough thought went into blending them into the roof line. 2: the louvers, as a unit, are flat. The side rails the fins attach to have no curviture to them and it seems they are made for a flat window, however, the 2011-2014 charger rear window has a slight curve top to bottom and left to right. In my honest opinion, they either grabbed something off the shelf that would "kind of" work and "close enough", and/or they just didn't spend the time for research and development. A few people have commented on them telling me that they look great on the car. So with that, at least it's a partial success. I wish I could post pics, as a picture is worth a 1000 words.