stainless steel is fine, but a bowl for stb w/ lye might be a little precarious, and possibly messy, definitely stinky if using naptha. the problem is too large surface area on top. in a #2 HDPE jug, the jug can be capped, and it is easier to pull solvent from the top. and it can be capped for extended periods of time without unwanted evaporation or fumes.