Holy Space Balls! I just drove my car with new Avons (and FIA wheels) on, and the difference from BB's is absolutely ridiculous. It is a night/day experience.
Of course, my tittle is facetious. More than one guy here has written about how much difference lays on Avons (for the better) and it is so true. Better handling, less noise, less rock chipping going on, you name it.
I do not see me going back any time soon...
Hector