The 2013 BMW M5 and M6 Coupe and Convertible are, unquestionably,
very good cars
. It appears, however, they are fitted with faulty oil pumps--which may fail so catastrophically and suddenly as to result in "severe engine damage" due to a complete loss of oil pressure. Accordingly, BMW has decided to stop all deliveries of the cars and to advise owners not to drive them in the interim.
That's not good. It's also not something that appears to have a quick and ready fix. One owner in the thread documenting the issue at Bimmerpost
says he was told not to drive his car, the dealership would come pick it up--and they might have it "for a few weeks."
That's also not good. It's not just an inconvenience to the owners--most buyers of the 2013 M5 or M6 probably have another car or three in the garage--it's a black mark on the company's reputation, happening nearly at launch of the 2013 model-year cars. First impressions are important, and this isn't a good one.
The notice outlining the problem to BMW dealers says more information will be coming shortly, so look forward to more on the problem, the solution, and the time frame soon.