The 320d will be very different to drive.
The extra torque will give you better recovery. So when sitting at 50, you can just leave it in 5/6th and put your foot down and go.
The narrower power band will also mean you need to change gear more often lower down to make sure you are in the right rev range.
You will feel the torque difference. Depending on your driving style, this may appeal to you or it may not.
Give a 320d a test drive and see what you think!