you are spot on right, the OM606 is very very refined, smooth, vibrationless and extremely long life, Theres a guy here in my neighborhood whose OM606.912 faced the sunken valve seat problem after 215,000 miles, so he invited me over to assist him in removing the cyl head. 3 hours later the head was on the bench and I was amazed to see that the original cross hatch on the cylinders were still there after all those miles. technically it was not broken in yet. And disassembling the head would make you wonder in awe - Twin hollow camshafts, 4 valves/cyl, ultra light valve springs, seats and retainers, filled valves, pentroof cylinder head and injector in the centre.. Amazing design for an IDI - no wonder the engine revs to 5500 rpm so quickly.
I also like the OM606.962 - yummmy pull and an ECU remap proves it to become a gourmet dinner. But you simply cannot beat the dead simple mechanical reliability of a W124 chassis. I consider it the LAST MERCEDES BENZ VAULT QUALITY AUTOMOBILES.
