I used to have one on my Datsun 240Z, and while it was a godsend here in southern TX (blocks off heat and sun, and kept nosy neighbors from looking into the hatch), it tended to 'flutter' and I hated that I had to screw it into the hatch.

Considering the small size of the hatch window, and IMHO, the enormous blindspot, I wonder if it would further block off even more of the rear view for the driver.

ALTHOUGH....I DO like the 'smallish', flatish look of the photoshopped louver (the old ones would make the cars look like a rooster's comb)...wonder if some wunderinventor can figure out how to make one of soft rubber that can be attached even temporarily, like a plastic (sorry for my lack of semantics - not an engineer). Having one that you can stick on and off might be something someone might be interested in, almost like an external sunshade for the rear glass.

Just a thought...