I am considering building a UDS in the future, but I am curious about something. Which is a better barrel? Food Grade Lined, or a Gas/Oil Unlined? I see alot of folks are getting a food grade barrel that has a liner, which is then burned out. Alternatively, folks getting an unlined barrel seem to have ones that had gas or some other chemical in it. My thoughts: the liner is presumably some type of plastic - I would imagine that, in the burning of such a material, you would leave behind a substance which is just as problematic as leftover Gas/Oil residue. On the one hand, I think it does not matter, because the barrel is getting all previous materials removed via burning/scribbing/wirewheeling, then covered over with high temp paint. So, does it matter at all?