Just found this surfing: http://members.xoom.com/minimopar/oilfilterstudy.html Doesn't have Mann, Mahle or Bosch (yet) but he does do a good job dissecting most other filters out there.... Cheers, Richard 88 90Q "Hannu" - K+N, new vac hoses, lubed U-Joint, still 0.0 bar.... 88 Golf GTi - PRO Rally