The question is whether or not the Bosch filters are the same as the OEM filter (such as the Mann spin on) and not where they are made.
As I said, the Bosch spin-on for the M103 appears to be identical to the MB labeled Mann filters I get from Caliber Motors. The Knecht filter I bought with the Bosch was made in Austria and appears smaller and of a different construction than the Bosch/Mann filters.
Bosch or Mann filters may not be the best but I wouldn't think they are bad either. If the Bosch is junk than so is the Mann spin on sold by dealers.