I'm surprised at how obsessed people are with the way they look. I have a 350ZR because of how it feels and performs. My windows are made of glass and clear so I cant really tell when they are up except for the reduction in hearing loss from the lack of noise. Then again I've been to many concerts without earplugs which is just as bad for hearing loss and tinnitus. Wished I was smarter when I was younger. Windows do go down below 40 mph unless it's cold.

 

I think the one thing you can take from all the replies is that it's personal preference.
Windows up at speed is definitely a winner though... Less wind buffeting and noise and I'm sure there's something happening with gas mileage with them up?!