MagicBox Acetone Bath to Smooth 3D Prints

[Teledog]

Newbie here (Flashforge X should be here next week)
Watched a few YouTube videos on home-brew vapour polishing.
It seems they almost all use a glass jar or metal tin with the acetone boiling at the bottom.
They consistently seem to be smooth on the bottom and rougher on the top
I would think this is because of the temperature differential from the bottom to the top.
Has anyone tried insulating their jars/cans & letting the temp stabilize before tossing in the ABS?
The unit that Timaz posted seems to be insulated ( and perhaps internal fans for circulation?).
Also, it seems some folks use nail polish remover, and others real acetone.
I would assume real acetone would be more consistent, as nail polish remover has varying contents of acetone.