I think JW Whitney is going to sponser this thread.
Why not look into Crown Royal air fresheners for the rear window? Perhaps some fuzzy dice? How about light blue spray paint for your dash and door pulls on the interior? Anyone have a tutorial for installing Dingo Balls around the windshield?
Seriously Jeff, why check with SolaraGuy Peeps overs something small and a matter of preference? We don't tell you what to wear to school in the morning. You need to have a vision of what you want your ride to look like. Then execute that vision. If that includes window vent shields, great!
In Japan, these are on just about everything. Including Taxis. But the Japanese tend to smoke in their cars and typhoon season makes cracked windows a pain. I don't think they do it for "style." This should be your case. If you have to smoke in the car and want it, just do it.
The only thing important here is that YOU like your ride. There is no right or wrong because of popular opinion.