quote: I want a reasonably factory-looking car, so I'll have to be content with lesser results.
IMHO looks are overrated.

I was thinking of a bumper sticker that says
"Proof of Concept"
or maybe
"Looks are Overrated"
My MPG have improved a lot by not worrying to much about the looks.
I have been able to maintain a pretty constant trip average of 75 MPG on a 30 mile almost daily trip doing approx 60 MPH.
I do get a lot of "WTF" looks, and quite a lot of picture taking while they are driving, even a few thumbs up.
Its really embarrassing the first few 100 times, after that I just ignore them.
To me the MPG is the only thing that matters.