The original 2012 F10 M5 got the 7:55 lap time.
Since then, Competition Package for the F10 M5 now has a time of 7:45 around the Nordschliefe.
M6 without Comp Pack is faster than 7:45 and with Comp Pack who knows probably another 10 seconds faster.
Awesome that they reportedly got the new M4 to be 15 seconds faster. I think it's a great achievement. Would love to drive a new M4 on the Nordschliefe one day too.