Last year I found a great deal and went a little unorthodox.
Bought Michelin PA2s in 245/40/18 front, PA3s in rear at 265/40/18 on oem rims. Bought the tires for $500 total, new from Town Fair Tire clearing out their stock.
I live in Manhattan and the car is used on weekends only, but wanted the ability to go skiing.
08 E90 M3 Interlagos Blue
99 E36 M3 Cosmos, #2--Sold
99 E36 M3 Cosmos, #1--Sold