After two E91's I would say that the cargo area is far better than the 3 series touring...
And the interior quality is fine, in fact all teh areas that you actually touch are better than the 3 series, however the area around the gearstick is terrible, really cheap and nasty and a real let down, but that is the only place.
Cup holders I am not fussed about, it has one that will hold a large McDonalds coffee and each door bin has a section at the front to hold a bottle of OJ or a can of Coke etc.
The drive is 95% of the 3 series and the comfort is far, far better.
Just been offered a 3 litre diesel sport touring with all the toys as a swap as I was not getting on with the manual gearbox, but decided the 3 series would actually be a step backward.
I have only done 5000 miles in mine, but already I know I love it.