Lol, I now also have a merc too so I can compare all 3
Nice to hear of your A6, I’ve learnt that Audi stopped shipping those petrol V6s this way pretty early on. So they’re a rare commodity. The 640 has one of BMW’s most regarded straight 6 engines - N57.
On paper the 640 has more horses and more torque, but heavier and 0.1sec slower from 0 - 60.
the A7 feels much more instant in terms of trottle response. It gears down and takes off pushing the head onto the headrest. Beamer also gears down maybe even more readily, makes a far better sound but the take off is less instant. The difference might be the A7’s duel clutch vs the 640’s sports auto.
A7 is also overall a very highly refined car in comparison. The ride, the interior, the drive..
The A7’s engine sound was horrible. 640 sounds so good in comparison I often drive with music switched off!
I must add, I drive mostly in sports mode, both cars (why buy a 3L petrol and be stingy on fuel
![Razz :P](./images/smilies/tongue.gif)
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