I have them in my Mercedes for 1 year and like them enough that I also put them in my Vlovo (as an experiment).
There is a least 2 threads on them.
Suggestion: Do the complete rebuild job on the Injectors including the setting of the Pop/Opening pressure. Just swapping the Nozzles may or may not work.

__________________
84 300D, 82 Volvo 244Gl Diesel