Are most people going with 20" aftermarket? If so, what is the main reason. I mistakenly picked the stock 21" rims and am now trying to figure out what my winter options are. I should have picked he 19" rims for winter and then would have been able to choose from all these awesome looking options.
So far the percentage is:
19" - 17%
20" - 41%
21" and larger - 42%
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No issue with running 21" for summer. Both 19" and 20" have some good selection of winter tire. However, 20" will defiently give you a better look, and the sidewall still can be fairly thick to give you a nice cushion. What I would suggest is to pick the size and type of the winter tire you prefer, and dial in the wheel later to pair with the tire.