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.
'08 E90 M3 - Alpine White - Sold
'13 E92 M3 - Silverstone II - Sold
'04 E46 M3 - Jet Black - BBS E88, KW Clubsports, Brembo BBK, SuperSprint Exhaust