Firstly both Don and Baz, love your cars. I like the big wheels look, but then the classic 17's are great too.
Anyway, here is a few links with regards to 'not all same size tyres are the same size'. Open to critisim here... after all... its the internet. I have focused on the Sumitomo and Goodyear GSD3 as this is what I was looking at comparing.
Then also a pic of mine with 285 40 17 on 10 3/4 rim.
Sumitomo VS. Goodyear GSD3 [pics] - Corvette Forum
Google Image Result for http://img.photobucket.com/albums/v335/JasonWW/99%20black%20TA/315sumitomos.jpg
