My 325xi has 17" rims, but 16's will fit it, but I think 330's need 17's. I put a used set of Dunlop M3 RF snows on mine this year and it has been unstoppable in the snow and we had a lot of it in Wis. this year. Get some dedicated winter wheels/tires and enjoy it.
2003 325xi StahlGrau metalic almost modless, wife's DD. 1998 328is lowered, X-brace, Sparco strut brace, HIDs, AEs, almost everything blacked out, my DD.