As a male who has done several workups of strength training in my life and who has been doing PBF exclusively since september I can assure you that PBF will give you some unexpected gains. The progressions are more intense than you probably think. I consider it high intensity, low volume.
I am currently worked up to the highest levels and getting ready to order a 50 pound vest to repeat(once I master plyometric pullups and muscle ups).
As far as strength and muscle gains I have gained Some great shoulder and ab strength. My chest and legs have always been incredibly strong and I have maintained that while gaining skills at moving my body through space.
Just jump in and enjoy the days off at first(your body probably will respond better than you imagine to lowering volume), as you progress you will find that you need every one of those days off. Enjoy and good luck with your journey!
Integrity is what we do when nobody's watching.