Personally I would sell the 2009 and roll that money into another vehicle to drive if you need one. The E320 is a solid vehicle and should run for many more miles. Accidents can bring out problems later down the road.
I bought an ML a while ago. It was in an accident but it was never reported on Carfax. I could tell because of overspray. I didn't care and still don't. About 2 years in, the paint flaked off the bumper. The repair shop didn't sand the gel coat and prime. They just opened the bumper and sprayed. It was "fixed correctly" according to how you can paint a bumper - but it wasn't done right.
I bought an ML a while ago. It was in an accident but it was never reported on Carfax. I could tell because of overspray. I didn't care and still don't. About 2 years in, the paint flaked off the bumper. The repair shop didn't sand the gel coat and prime. They just opened the bumper and sprayed. It was "fixed correctly" according to how you can paint a bumper - but it wasn't done right.