After 10k km with a catch can , vented to the plastic ring between the rubber parts in the intake.
Short : nono!
There is simple not enough flow and vacuum at all rpm. Tube from cylinder head got mayood very rapidly and pressure build up.
Bye bye vcg and hello oil leaks.
Now changed to catch can and full vacuum from distribution piece....
That's my story, remember : cold around 5 degrees C and very humid, so lots of condensation in the system.
If that doesn't work, back to oem and give the car to the misses 1x / week. She drives longer distances.
I have to fold myself in the Z3 then...