Oil Filters????
Back in the mid 70's I was a test tech in the engineering lab for a company that made oil coolers, tranny coolers and thermostats for the automotive industry (and heat exchangers and control valves for the aero space industry). We had a couple of large wind tunnels (one was big enough for a deisel tractor and had a chassis dyno) and some pretty large flow benches, we were always doing contract testing for companies because of our capabilities.
Lee (remember those guys?) came to us about doing some testing on their oil filters in comparison to the leading brands on the market. There motivation was to be able to say they were as good as anybody elses. We weren't capable of doing the full SAE test regime for oil filters but we did what we could. We tested every brand we could get our hands on (used the PH8A size filter) and basically the conclusions were there was no appreciable difference. That's when I stopped worrying about the brand of the filter.