As we all know all cars can have issues, more so if you buy a bad one. You will get a good one for 16k, most people opinions are formed from reading a horror story on the Internet. If I want to buy something I listen to owners and specialist that see these cars day in day out.
For some reason people think they break every 5 mins and bankrupt the owner!.
With the mondial warranty you don't have to use a main dealer either, specialist is fine so long as genuine parts are used (which most do).
I took a BMW tech with me to buy myne for peace of mind.
I guess it's personal preference but I drive myne to work in full auto mode in setting 2 on the gearbox and its great, relaxed drive. Then in M mode it's setup for s6 paddle shift.
I get 220 miles from a tank of fuel with mixed driving and usually average 18mpg, my 530d was 30mpg average and with super unleaded being about the same as diesel I didn't see it being a massive deal for a 5ltr car.
Only other thing to factor in is oil, they do use oil and it has to be the proper castrol edge stuff which isn't always in the shops so best to stock up on the stuff and always carry 1 ltr in the boot.
Try and get full leather, not to be confused with extended leather, it transforms the interior as it includes leather dash and door cappings, with out it you the interior is boring and its like being sat in a 530/535d etc. this was a 5k option and I would not own one without it.