First i'm thinking 1mm thick which is .03937", 19 gauge is .0437" too thick, 20 gauge is .0373" too thin by .0024" but rather close. I find this rather thin material. Now onto the volume and it must be OD specs at 20" x 20". At 20" diameter that is 314.16 sq/inch surface area rather large allowing for a faster evapoeration boil off rate during your boil. Next at 20" tall this is 6,283.2 cu/in total area to the brim of the 20" mentioned. With a gallon taking up 231 cu/in of area with 6,283.2 cu/in of pot volume this comes to 27.2 gallons. Filled to 25 gallons your 1.617" from the brim or just under 1 5/8" rather close to the brim before you add a 4% liquid expansion so stirring must be gentle without any waves or else you'll splash over the edge. In the stove your dead meat by the War Department I know first hand. Last thing your at $159 investment well less by $0.05. A rather large volume pot yes but that is the only good feature I see in it, sorry that is my direct feelings about this pot. You got me beat in volume as my Keggles will only hold 22 gallons under operation allowing a 2" space below the 10" cut top. Kegs free as well the labor and welding them myself besides a thicker material.
Bottom line I would look for best being free kegs and build your own system.
Then brew on.