On Wed, 13 Jun 2018 12:58:05 -0700 (PDT), wrote:

I have a Navian tankless water heater that I have had for about 8 years. I have had nothing but problems. I want to change it out to either a Rinnai or a Rheem water heater. I need about a 9.5 gpm or greater at 199,000BTU rating.
I already have the 3/4" gas line and the 3/4" water line and the condensate drain set up plus the 3" PVC vent lines so there is no reason to discuss these.
My question is which one is better. I would like one with a recirculating pump

Did you retrofit this tankless into your home OR was it new
construction? As to the brands of choice, I've never heard of Navian.

Your problems might be the planning, design and execution.