5GT 530d driver here. From what I see on the roads and on here I am somewhat of a rarity!
Great car to drive, had it about 5 months and 7700 miles. Average mpg 33 (low but I do drive it hard!)
The space inside is fantastic, even behind me (6' 4") there is room for a tall adult, and for the kids it's like being in a limo (their words....)
Downside - the handling is not great, can be a little skittish on the bumps - or I may just be going to fast - but as a motorway cruiser it's awesome.
Lets hope there are a few more of us!!