answer:I don’t think it’s performance, but I’m not sure. My husband loves that look. I find it frustrating, because you are much more likely to damage your wheel on a curb. If you hit a curb with your tire no big deal (I’m talking about at a very slow speed and just a tap) if the curb hits the wheel—scratch. It’s not like I hit every day, but in 10 years I’d say it’s happened 3 times between the two of us. As far as I know it’s just a style thing, but I might be very wrong about that.