Point noted on the strainer location with the 25AUB. But the N45B-M1 and N55B-M1? Not seeing any difference including the flow/pressure drop. No guidance from Watts. I wonder if its some regional thing; this is what’s used in our .
I am retrofitting my home with a field-constructed PEX manifold system (1” to 3/4” branch) and also streamlining the 1” main run back to the service entrance, so I figure on upgrading the PRV to lead-free as well.
Sorry, I didn't have time to read over the PDF file. For the most part they are designed a little different all three seem to have a screen. I would go with the 25AUB. Strainer can be cleaned for mt eh bottom and also allows a pressure gauge if needed.