Agree with above, definitely electric steering is lighter on the F10. If you prefer a weightier feel, just press "sport" (provided you have set your "sport" to include chassis) and it will give a similar steering feel to that of E60.
I drive min. 100kms a day and in 12 months in my F10 520d, and have clocked over 37,500kms so far.
It is great not having to visit the refueling stations as often as before.
And, with the diesel torque, overtaking on freeway or climbing a steep incline is not a chore.
Sure, off the line there is a bit of a lag (I feel it every time at traffic lights/toll/hump stops/slowdowns), but I am not doing a 0-60 race in the city. I am doing 100kms on freeway.
As for mechanical expertise, the authorised dealers have trained their staff on the maintenance of the diesel engines but can be very expensive once your BSRI has expired. But I understand that some of the trained staff do a bit of moonlighting.