Under 4 weeks to get past 1200 miles.
Of course I "Broke it in" about a week after owning it.
Lease + free maintenance means I care very little about the long term reliability of this engine. I'll leave it to BMW engineers to worry about that.
Current: '15 M235i Vert
Previous: '13 335i, '08 TL-S, '00 Corvette