I used to swear by K/N air filters, now I swear at them... I do however, love K/N OIL filters.
Its not about restriction for me.
Its about the oil haze coating my intake components from the oiled gauze filter, in turn allowing dirt to stick to them and then introducing it to the top end of my engine.
I had a UOA come back years ago from one of my JEEP's with an extreme amount of silicon, BS's first question was if I had an intake leak then if I was using a K/N AF.
It was new, therefore not over oiled, and it went in my trail beater as they do help in dirty environments where longevity is not the goal but rather performance is.
Now... you will find tons that say "I have used them forever with no issues", most of those do NOT do UOA's to even know or they sell a vehicle when it hits 25k mi or even 100kmi! Yet others do UOA's, and have no issues as they see it. Great, to each their own! Me, I want to engineer out as many issues as possible. I just stick with WIX these days and in applications where I use CAI's I use the AMSOIL filter.
BTW, I too run AMSOIL SS in my CX-5. I am considering moving to the AMSOIL Euro in 0-30 for both the CX-5 and the LEX.