I would choose between the Muff Pot and Hot Pot. I have both. The Hot pot is a little wider, but not as tall. The Muff Pot is a tad more narrow but taller. Both about the same length. I've found the Muff Pot to fit into places better on both my Cats and Poos over the years. Unless they upgraded the material they make the bases out of in the last year or two on either pot, then they can still crack and break over time and abuse (usually crack where it's strapped down). I have not had a base yet that has lasted a full season (~50 days). Usually either company will replace it free of charge though. Instead of worrying all the time about mine, I just made one out of steel that is actually more thin then the chinese metal they use in the factory ones. It's held up perfect over the last couple years.
The c-clamp can loosen if you mount it on something without a good foothold, like the taper on a pipe. I was able to mount mine directly on top of the can and use long C-clamps that I secured to the can spring steel loops. 450 miles and hasn't come loose yet. Also warms my food quicker than I would have thought in that location. Both are "fairly" leak free, but I wouldn't want my sled upside down for any length of time if you are cooking liquids in it. If so, use a Reynolds Turkey oven bag from the grocery store.