Don't understand why you would. You're keeping your M, so what's the point? A winter car? I see you have a 335xi, so...
If I chose to spend my money on more vehicles, I would want more variety, something more different from the M.
M3: Active Autowerke filter, Dinan underdrive pulley, Dinan full exhaust and software, 3.45 Differential, Springs, Brakes, Dinan/HRE wheels, 275/30-19 w/10mm spacer, 295/30-19 w/3mm spacer, painted front reflectors, 30% tint, Escort 8500i & Lidar Jammer, LUX H8 V5 halos, Euro rear foglights, 3M ClearBra.