Oil Filter Tests by river_rat on BITOG Forums
Japanese filters are sieves in my (admittedly limited) experience--Same with Denso.
I suspect Filtech makes excellent quality media--to order.
If the filter manufacturer specifies 80% efficient, they provide top notch 80% media.
NG/Wix...I pretty much ignore their (probably) outdated published betas.
The media looks to be in the efficiency range of a Purolator Classic/K&N/Mobil 1 class in every test, time after time. (with the exception of some media leak-by inconsistant results with three I had)
Also, looking at the media through the microscope, and measuring thickness, it looks very good and in-line with the filtrate results.
They are good filters.