I'd agree, the mid range is something to behold, very addictive!! If I do give it the beans, I get more torque steer now which is hardly surprising given the large number of horsepowers available through my front wheels, but I find the car is much less unwieldy than pre-remap at junctions etc, where getting underway required more finesse from my feet on the pedals.
It really is bad practice to rely on torque from low speeds, I call it mechanical sympathy, ie to understand what is happening when you put your toe down and treating your engine, clutch and gearbox gently as a result
As for the MPG, my journeys are always of a decent length (48 miles each way 5 days a week). I've driven Benitto 15k miles since August!
I have used Fuelly
from day 1 with my 159 because it was always my intention to get an AHM (or similar) remap. I wanted to be able to see the improvement in fuel economy and my first full tank, peppered with "exhuberent" and erm "making good progress" type driving still gave me my second best ever MPG of 40.2, so I would agree that around 44 ought to be easily achievable without driving like a pensioner in a Micra
That will do for me, I can relax and enjoy the car rather than continuing to be the fuel consumption obsessed bore I have become!!