What I believe I would do: get 2nd opinion on the turbos for sure, if salvageable/possible I would have them rebuilt. Since the DEF box has to come off, I would determine if it is bad or not. A couple of parts are replaceable, if you are so inclined, if the whole box was to be replaced or plan to anyhow, I would delete and program. My $0.02 FWIW. love mine is e70 2011 35d