I stuck to the recommended break-in. 36k miles in 4 years on my '08 (now sold) and had to add 2 quarts of oil during car's life-time.
'04 E46 M3 - Jet Black - Sold
'08 E90 M3 - Alpine White - Sold
'13 E92 M3 - Silverstone II - Sold
'13 E92 M3 - Alpine White - Ohlins TTX, AP Racing BBK, Cobra Seats, Akrapovic GT4, BBS E88, Volk TE37, OE GTS - Aero, 1/2 Cage & Seat Delete