I think the FASTLANE plug is a Bosch F 8 KTCR with a 1mm gap
The MB manual states a Bosch F P DCO with a .08mm gap.

The MB Bosch F 9 DCO plug may be hard to get, or I wonder if only through mercedes dealerships at what I have seen at fifteen to seventeen dollars a plug.

With these high energy computer controlled ignition systems I wanted some input from the list on which way to go.

I may check out the Beru and Champion plugs (hope they are easy to find) listed in the owners manual if I cannot find the Bosch