Performance issue and M550i don't fit into same sentence
As a 1.6lt G30 owner (8.3secs 0-100 and 6.4 with a Stage1 tune) it really sounds awkward
I don't know if BMW puts a limiter on cars but my BMW bike (S1000RR) had an electronic limiter until the end of break-in period. And dealer cancels the limiter on the break-in maintenance which also activates slick mode after that. Only explanation that I can think of is this one