One thing to keep in mind is that filter media, and efficiency, may vary (a little or a lot) between one application and another, or even over one period of time or another (perhaps a change of media supplier or???). If the old Wix spec sheets could be believed (today, the numbers are a little suspect), there were wide variances in the efficiency specs for the filters by application.
The best idea, if possible, is to ask for specific data on a specific part number. I have done that with a few filters and in a case or two, the specific number was in variance from "published" generic numbers.
The bottom line is, if you are pedantic like me, there is no instant gratification of the desire for detailed product knowledge.