Finn. The little filters work fine as long as you have not modified the oil flowpath from the original design. Most of the pump output bypasses the filter and goes straight back to the sump via the relief valve. It is a smart design in that all pump output goes through the heat exchanger for cooling capacity but only the oil required by the oil gallery is filtered. Some users do modify their system to filter all the pump output, but this requires a much bigger filter and is kind of overkill.
Andrew