Trust us. 20"s minimum on the F10.
When i went to 20" non RFT from my stock 19" RFT's i didn't even notice any change in comfort. If anything the ride might actually a little better. 21"s looks perfect but only if the roads are pristine by you. 20"s is the best compromise.
2014 LCI 550i M Sport | 3D Design Front Spoiler | BMW Performance Black Grills | BMW Performance Trunk Lip | BMW Performance Diffuser | Painted Reflectors | Wincos 30% Tint | Supersprint Exhaust | ACSSprings | MORR VS8.2 Rims 20x10R and 20x9F | Michelin PSS Tires |||More Photos of my car here|||