I think this is an interesting question and realized that I would always start the car before putting the top down. Today I put it down before starting the engine after reading this post. Hmmm - no difference in performance - so is it simply a preference thing?

I also like to have the air (or heater when needed) on when I have the top down, so starting the engine brings all systems operational. I recently drove a friend to her office and she was mighty surprised to find cool air coming her way while the sun was beating down on us. Not terribly fuel efficient, but sure is comfortable. Alicia