I ran 6's all last season, and the beginning of this season on a Super Sportsman. Just switched over to 8's before our last race, and the difference is night and day. My mower hooked up better out of the corners, and handled better all together. I'm a light driver (150lbs) so I can use all the tire contact patch I can get. With a heavier driver, It may not make as much of a difference.