After almost a year the inline e36 m3 filter has been tested.
Did one long trip to alps and 2 ~1h session track days in warm weather. And lots of backroad driving.
In total ~10k km.
Few months ago changed the filter and opened up the old one - no debris at all.
Few small black pits but probably came when opened the filter up.
For the clip experts, both clips were nice and tight
No leaks at all
Also Inpa and Ista didnt give any codes.