You should have changed it to Sport Mode for faster acceleration and better handling. The Eco Mode saves fuel and the engine never revs as compared to Sport Mode.
I am driving a lot in Germany at higher speeds, and that is when the fuel consumption of a petrol engine exponentially increases compared to a diesel engine. So out of fuel economy, and the fact that diesel is cheaper in Europe anyway, I prefer the diesel engine more. But in a fun car, not for everyday use (like a Z4), it is petrol all the way. :)
Nice top speed with 1.6 turbo. V gear is better for top speed than VI because of higher revs (more hp) right? I wonder how C200 with new C-Class will behave in similar test. This will be 2.0 with 300Nm of torque and about 100kg lighter car so probably slighlty better. Hp with 2.0 engine in the same level as here. Weird but base model C200 is rated as 184hp. Hopefully 300Nm will make a noticeable differance. This dash with nice speedo looks way better than with a new C class. Shame they changed it this way.
What kind of package do you have? The Basic and Elegance package have a black speedo, the Avantgarde package comes with a white one. From the C-class Basic I drove I have videos that match the description of your speedo.
Habe ein W204 CKlasse Coupe 6Gang mit dem 1.8 Liter Motor. Also irgendwie schein mir der 1.8 mit 156 PS agiler bzw. besser zu beschleunigen im 6ten Gang.