I recently towed a 2520 cross country on tandem axle trailer with surge brakes with a F150 rental truck with the V8. Towed fine but the anti-sway component of the Towing Mode saved my bacon a couple times when trucks blew by me (I kept it around 65 and speed limit was up to 80 in some places) creating a sucking then pushing effect. The instant it got squirrely, the anti-sway kicked in, slowed the truck down, and the sway went away like magic .
If you are loading the deck up with tanks, I would definitely test ride both the 2320 and 2520. Way more deck space on the 2520 and towing concerns would be at the bottom of my list for pro and cons on the two models. For me in California, the permit issue is really a non-issue. Annual permits are available for a low cost and if I were towing it more than the couple miles to the ramp, I would consider it although I have never heard of anyone getting a ticket for no permit and I researched this issue before I bought the 2520. One thread I read the guy said he was pulled over for a trailer light or some other reason (can't remember) and was never asked for a permit. Of course I just jinxed myself and will probably get a ticket next time I tow ....
If you are loading the deck up with tanks, I would definitely test ride both the 2320 and 2520. Way more deck space on the 2520 and towing concerns would be at the bottom of my list for pro and cons on the two models. For me in California, the permit issue is really a non-issue. Annual permits are available for a low cost and if I were towing it more than the couple miles to the ramp, I would consider it although I have never heard of anyone getting a ticket for no permit and I researched this issue before I bought the 2520. One thread I read the guy said he was pulled over for a trailer light or some other reason (can't remember) and was never asked for a permit. Of course I just jinxed myself and will probably get a ticket next time I tow ....