Hi. I'm looking to buy a 2011- 2014 520d/525d/530d. Iv heard that the timing chain can be an issue before 2013. Can anyone confirm this is true? Also I have my heart set on the larger screen but that obviously rules out a lot of the cars. Is it possible to change the screen? Thanks alot for reading I hope these questions haven't been asked dozens of times and everyone's fed up of them.