There are real advantages to larger diameter wheels if you need the space for huge brakes. Purely visually they work for some people, But...the greater overall weight and rotational mass are big negatives for handling, stopping distances and acceleration. Harsh-ens up the ride too. 17's are just about a perfect size to balance off all the compromises of larger, or smaller, wheels and tires. With a mostly stock suspension and brakes, high quality 17 tires will give the most bang for the buck.