I've had a string of BMWs, then a 6.2 C63 Estate and now back to BMW again.
Don't kid yourself on the fuel economy, the B58 is remarkable on that front. Knock at least 5 and probably more like 10mpg off any given scenario in comparison to your 340i.
The 6.2 and 4.0 use almost the same amount of fuel when driven hard, think mid teens. When driven lightly the 6.2 remains thirsty and the 4.0 will go high 20s or low 30s on a long run without too much difficulty. I used to get low 20s even at 75-80mph in my 6.2.
If you want to experience something unique then get the 6.2, the engine is like nothing else. The 4.0 is a much better handling car due to the double wishbone suspension, it corners far harder. The 4.0 feels more like any other modern car, the engine doesn't rock the chassis and it's electric instead of hydraulic steering.
I'd be happy in a 4.0 but it's more than I wanted to spend. I feel like a turbo six is the perfect compromise for the road, still more than powerful enough when tuned and also usefully economical.
Here's a more detailed write up I did.
What follows are my thoughts after a five year ownership of a 2013 C63 AMG Estate, much of it is subjective but represents my views. Buying My birthday is early December and back in 2017 I spent my day off going for test drives in a B8 RS4 and the C63 I ended up buying. I had no intention of...
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