I have a 2020 diesel Rubicon, really love the torque and the mileage. If the 392 got better gas mileage and had a 4 to 1 transfer case I would consider getting one also. The extra money doesn’t seem worth it for only 30 more foot pounds of torque. The horsepower would be better used in the Mojave.
From the perspective of a former diesel mechanic for 30+ years, who also used to never drive anything but diesel personal vehicles? Stick with a gas motor, especially if you plan on going the long haul with it.
I do overlanding and longer trips and therefore the diesel is a clear winner for me. Diesel is great for this and the miles per tank makes diesels a winner for a jeep that is not daily driven and taken on trips.
if you daily drive, the 392 would be better. Gas engines handle the short runs/drives better than diesels. The exhaust button will release any inner child that exists in you. 392 is most likely going to be less maintenance down the road.