[MetroMPG]

Originally Posted by Arminius

Here's an article on this topic. Halfway down they mention Consumer Report's extensive testing on the issue.

http://www.bankrate.com/brm/news/auto/20050804a1.asp

Interesting link, but the red flag went up on the "GasBuddy" guy's quote:

Drive at speeds over 55 mph with windows down and you'll decrease fuel economy by up to 20 percent or greater."

20% sounds exaggerated.