Larger, wider wheels (rims for ya old schoolerz!) are great for two purposes: Looks, and racing. Beyond that, they are more prone to road damage, and to being pulled to one side or the other by road imperfections (potholes, dimples, etc). Wider tires have a contact patch *perpendicular* to the direction the vehicle is traveling. Narrower tires have a patch *parallel* to the direction of travel - more ideal! Wider tires/wheels require stronger centering forces (caster, SAI) for straight-ahead stability. Narrower combos impose more weight per sq. inch in a narrower patch, and tend to want to straighten from turns naturally. Moral of the story? Unless a vehicle comes with low profile wide wheels and tires engineered that way from the manufacturer, stick with the OEM wheel and tire sizes, you won't regret it!