I had an E250CDI in 2010 as a hire car a few years ago; quite nippy, but noisy and uncouth. Fast forward to last week - still a E250 CDI, but the 2014 model. What a difference! I could hardly hear the engine and it's 4 cylinder thrashing till my right foot was flat on the floor. When I test driving the W204 250CDI, they all sounded like tractors to me, thats why I got the 350. If they've pulled off the same trick with the W205, then it'll be difficult to justify the 6 cylinder version and I'd have to change my handle.... The interior is nicer, rides much better and is overall much quieter and cossetting. In summary : very impressed with the current E250CDI.