I’m hoping to collect a 2016 E63 estate next week and this thread makes for sobering reading.
Don't let it put you off, it's a great package.
These are minor issues in the scheme of things and are to be expected in modern products where profit is the only thing that matters.
Seemingly from the higher milage M157 units in the USA, they do appear not to have 'big' problems other than the odd bent connecting rod issue but my feeling is this is more likely with owners who have mapped, ragged etc etc.
For the price of engine oil required in these things (v cheap in my opinion) the re-occurng theme is to change oil regularly .