To get me to drive a gas W211 it would need to be an E55.

You give up a LOT of torque going from OM648 to M112, while it is a terrific/reliable engine, its also fairly boring. With rear wheel drive its probably ok but a 4matic W211 is a slug off the line with M112 OR M272. Its a heavy car that needs some torque to get it moving. My W210 wagon isn't slow....but it feels like it compared to my diesel and even my Metris (lots of torque with the M274 turbo off the line) The 7 speed trans helps a lot too.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)