I already run a set colder....sort of cheap insurance...but should I run two sizes colder?

Did have #6 misfire around 128 while beating on a 750i two weeks ago.
Car went into limp mode....pulled off the highway,stopped at the light counted to 10 and prayed and started the car back up and been fine ever since.

Damn I was scared!!

Thinking about trading it in on a clk63 vert amg.
And staying stock! Getting tired of breaking stuff to go fast with the top down!