They're such fun cars. The OM606 with the 3.07 differential + overdrive is so communicative, you're on cloud nine with these things.
Do I think they're better than an SDL? Hell no! But they are reliable, quick once on boost, and a little bit more fuel efficient than a W126.
Don't ruin these fine cars with greasy garbage, please. At 5 - 10K dollars a block, leave 'em alone and stick to the straight stuff.
Long live the screaming 60x engines!!!
(I have to get off the 12 cups of a caffeine rush)