Good question. But how would you know?

Uh you do realize that we are talking in terms of particles that the human eye can't see right?!

When I tore my engine down and the internals still looked great it certainly didn't tell me my oil filter sucked . I've always used the Wix Racing filter . That don't mean it's the best , just means it didn't suck .

Bearings would tell a good story.

In all fairness, I don't think anyone said it sucked, I said 60um filtration is pretty lousy, and it is. Were the bearings measured or just visually inspected upon teardown? Better filtration is never a bad thing, as it's been proven by GM, FORD, CAT, John Deer, Allison.... Essentially companies who have invested millions of R&D hours into the benefits of increased filtration efficiency. IMO a filter providing around 60um efficiency would only go on a "racing engine", one that sees frequent tear downs. That's just me.

I guess my point was engines don't remain in good running order for that long if your filter is not doing a good enough job . I retract the pan .

I will be going to a new filter for the new engine . Not to proud to learn something .

point taken , what filter does an excellent job without being overly restrictive?

I read somewhere that the majority of engine wear comes from particles in your oil that were smaller than 5 microns. No clue if it was true but it made sense.

Either the K&N part number HP3002 or Royal Purple 1218. Both have very high flow and excellent micron ratings.