[DougD]

I noticed in the claims posted that as the sidewalls decreased, the tire widths increased. Not really a true comparison, now is it?

There is so much more than wheel diameter to determine which is best. Compounds, tire brand, offset, rim width, suspension settings, alignment, etc. Ever weigh a set of 18" or larger wheels and tires? Quite a bit heavier than 15s. Think this has any effect on handling? Can you say unsprung weight? You can't just slap on a set of wheels and tires and expect them to perform if the car wasn't designed for them.

The only sure truth is that you can fit bigger brakes. Otherwise there are too many variables. I personally have a set for the street and a set for the track.