I see this all the time on M3 forums. Most people think 19's look the best on the e46, but the more performance oriented crowd sticks with the smaller stock 18's or lighter weight aftermarket 18's. I will be the first to admit that most of the 20 inch BMW wheels look fantastic on the X5. They give it a much more aggressive appearance. However, there is a price to pay for that (tire prices, tire wear, rougher ride, more unsprung weight, etc.). I actually wish there was a little more of an OE compromise than the really wide 315 sized 20's and the skinnier 255 18's & 19's. I think a 19 inch wheel with a tire ratio of about 275 or 285 would look pretty good and be a nice blend of comfort/weight/handling.

On a side note, we just picked up an 09 35d with the stock 18's and the ride is very comfortable. I have a buddy with a 4.8i sport package equipped with the 20 inch 275/315's and he very quickly noticed how much more comfortable ours was. I have gotten used to the look of smaller wheels. To be honest, they really only look small for the vehicle when it is next to another X5 equipped with 20's. It sure doesnt look as mean, but it still looks good, imo.

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