I'd say as long as you have winters on...an extra 10-20mm of width won't matter. Mine are 245s out back (used to be 255s), and I go just fine. Car is heavier...but think you'd be just fine with a wider (and better looking) tire.
08 335i e90 TiAg/Black, Premium, Sport, Step, Cold Weather, BMW Perf. shifter/e-brake, M3 lip spoiler, blacklines, aFe intake, VMR 710s, Gloss black vinyl trim, black 3.5" DiMisa tips, Procede V5, ar Design OCC, ETS 5" intercooler (black), MTech wheel, rear bumper, and side skirts, Stett CP, Forge DVs, LUX 5.1, Ground Control Coil-overs, OEM split armrest, Raceland catless DPs, BIM Coded...