To answer the original question..none, zero defects.
My 22 month old 3D SE has done just a shade over 17k miles and has only just had its Oil Service.
It's used one pair of front tyres, the rears should last until I trade it in in April for a nice new 3D MSport in Carbon Black
Only negative is having to re-set the tracking every 9 months or so.
Other than that it's my favourite BMW.
PS I get >34 MPG