Anyway, today, I had a good chance of checking the tension/stretch of the leather on all the seats. They are all a bit baggy but nowhere near as bad as the driver's front seat which is, to say the least, really very bad and getting worse with use. It now looks completly wrecked!
I really feel that I've got a bit of a lemon as far as seat quality is concerned. I've checked 4 new F30 320d M Sports with Coral Red Leather at the BMW dealer and all of them were far, far superior to mine. I would say they were perfect.
I will mention this to the Warranty Manager. The car is booked for the 3rd January for them to assess, investigate and eventually instigate a fix.
Superman F30 EBII 330d M-Sport//Red Hippo Hide Chairs.