The other thing I hate was the outright lies on fuel consumption
All manufacturers lie. You need to take about 10mpg off the official figure.
The official figure for the E250 cdi is 61.4 but I think that is the normal version not the AMG spec one with it’s mpg dropping 17, 18 or 19″ alloys (i’ve got the 18″ with 265 wide tyres 😯 ). On a trip from the Wirral down to Bristol with the whole of the M56 as stop start and then doing 70-75 the rest of the way down the M6 I was on exactly 61.4. If you are “making progress” then expect that to drop to 50-55mpg on a long run. Still not bad and I think the sport is supposed to be 58 due to the wheels and tyres.
My daily commute is 21 miles there, 35 miles back (town in the morning, motorway in the evening) and I can hit 50mpg, just on a mixed trip of A roads, city, m32 and ring road in the morning. It is more likely it will do 44-48 and never lower than 40 when I leave late and spend 70-90 minutes doing the 21 miles due to traffic.
I would expect the slightly lighter C class with narrower tyres to get a few mpg more. That is with the 7G+ auto box (e-class has the same column mount shifter as Tesla).
One gripe I do have is even in manual mode the box barely lets you actually choose a gear as the software generally overrides but then again I hate trying to drive manual without a manual clutch. I am sure I could get incredible mpg on a manual but that is not what a merc is about. The paddle shifts are standard (only seemed to come on BMWs with the extra sport gearbox pack) and I tend to use them to shift up a little earlier than the gearbox as I can read the road ahead and shift down instead of using the kick down or the sport button.
The real killer on mpg is as soon as you go over 70 in any car the drag square rules really kills your mpg and at 80 on french motorways I would be 5-10mpg lower than driving at the uk speed limit. Sitting at a constant 50 I have had an average 74mpg (not instant mpg) but I was getting a good slipstreams off trucks and large caravans.