Grizz, Yes, I believe you are reading it correctly. My 3795 Cyclone is also max'd out at 18000 lbs. My F450 with automatic transmission has a 5th wheel capacity of 24,000 lbs. (But I'm betting that's at sea level and on a level road!) If the numbers are accurate (and they should be) the F350 and the Cyclone should be a good match with only a 200 lb difference, depending on how you load it of course. Since the F350 can pull 17,800 and the most you can load the RV is 18,000 lbs.
The numbers on my Cyclone say it weighs 14,000lbs empty. Then I add water, (110 gallons at 8.3 lbs per gallon), gas for the generator and toy, (30 gallons at 6 lbs per gallon). I’m already at 15,100 without my ATV (1000lbs), food, all the basement stuff. So you can see just with my ATV, water and gas I’m 18,000-16,100=1,900lbs left of “stuff’ I can put on the RV. That’s why I also use the truck to carry the extra water vice the garage in the RV.
However, I tend to err on the side of caution and figured at altitude, and extra water in drums in my bed, and not for sure how much my Cyclone really weighs fully loaded, if I got a 24Klb capacity truck, I could pull anything I would ever want to pull over any incline. Plus, I could do it without needing a Commercial Drivers License (in Colorado anyway).
I find with the 4.88 rear end, it is much easier to pull the RV, even starting out than it was with the 7.3L F350. I had to accelerate with the 7.3L pretty heavily to get it moving. With the 4.88 F450, I just take my foot off of the brake and it starts by itself.
I like to have as big a safety factor as possible when going down the road at 60mph, and the F450 with all the towing features satisfied that for me. And, being able to put 6000Lbs in the bed of the truck without adding airbags also made me feel safer. I also had a 24K lb 5th wheel hitch installed, even though I would probably never need the extra capacity, it makes me feel better!
Would recommend that when you do your cost/benefit analysis of a F350 vice an F450, call your insurance company and see if there is an issue with them or a big price difference, because they may try to call the F450 a commercial vehicle. Ran into this with my company, but logic prevailed once I sent them to Ford's web-page and they could see it was a pickup truck and there was no issue with them then insuring it for me.
(Also, don't forget that the family and "stuff' in your truck will also need to be considered as they will subtract from the total weight that your truck can carry)
Best of luck and let me know if you have any more questions for me. KH