@BuddyL33, rotary nozzles do have a low PR and take longer to apply water by design.
I would recommend you actually have a Net PR of .45 in/hr on your zone. Pending spacing, coverage, and pressure, the actual water delivered to your lawn on a zone by zone basis can be different. The best way to double check is to perform a catch cup test, which will not only give you the Net PR, but also the efficiency (DU) of the zone.
Hope this helps!