As a follow up to my 9-23-21 post in this thread, I will give you my current results. As I mentioned in the OP, I have a 2007 Monaco Cayman 36' PDQ with an ISB325 5.9 liter engine. I installed the AG 12000 on it back in July 2021. At the time I had 17740 miles on the rig. We now have over 34K miles and the module has performed great. Prior to installing the module we averaged 7.69 mpg overall pulling our Jeep Rubicon some 8300 miles. Last fill up our overall mpg was 8.10 over the last 16453 miles. I consistently run with it in the range 3 which provides the highest performance. I have noticed no increase in transmission temperatures nor do I have any issue with the engine overheating.
Attached below is a graph showing the mpg I have gotten with this coach since we bought it in 2019 with 4025 miles. Up to 9400 miles we were towing a Jeep Liberty. At that time we upgraded to the Rubicon and we saw a drop from 8.21 mpg to 7.69 mpg towing the Rubicon. The pale blue line is the overall mpg pulling the Rubicon after installing the module.