Sweet Gum seems to warp worse than any wood I use when drying. With that in mind thought I would try some Turners Choice after reading about it from several sources. They all implied that you could leave the roughout less than 10% thickness because it would hardly warp and would be dry in 3 days.
I soaked a 15" green Elm bowl in it for 24hrs. and it did as advertised and warped maybe 1/4" but took 12 days to quit loosing weight.
Thought I had found the ticket for drying Sweet Gum, so I roughed out a 17" Sweet Gum bowl and put it in a barrel of Turners Choice.
The roughout weighed 14# going in and came out weighing 15#. At $200.00 per 5 gals. this could get expensive but would be worth it to me if it wouldn't warp much like the Elm I tried.
As you can see it didn't work on the Sweet Gum as stated.
Also took 14 days to quit losing weight.
At $200.00 per 5 gals. vs $56.00 for DNA I think I will stick with the DNA.
DNA bowl when dried was 14 1/2 by 13 3/8.
TC bowl was 16 1/2 by 15 7/16.