I had problems with a couple of FRAM oil filters on two different cars before the oil filter study came out. I had gone to different filters even before the study came out.
When I did see the results of the oil filter study I was shocked at the internal appearance of FRAM oil filters. Now, I am not an oil filter expert-maybe FRAM makes the best oil filters in the world for all I know. But the appearance of the filtering media in those FRAm oil filters, the plastic valves, the cardboard endcaps, the few openings in the metal tube, etc., really turned me off. I felt that the WIX oil filters and Fleetguard oil filters looked much better inside. The Fleetguard oil filter internals I didn't see until much later after that oil filter study.