I'm researching and planning a UDS build soon, hopefully. I have a few feelers out looking for the right drum to use, but in the mean time I have a few questions that I haven't been able to find answers to while searching the site. 1. I see that everyone is using black pipe nipples and fittings for air intakes. How do you think brass fittings and nipples would fare? I don't mind spending the money for the iron stuff, but I have access to the same things in brass, free of charge. 2. Does an ash pan serve any other purpose other than ease of cleaning out the ashes? Does it offer any sort of protection to the bottom of the drum? I'm thinking that, for me, the best way of cleaning out the old ashes is the same way I currently do it on my offset firebox, a Shop-Vac. 3. If you were to build another USD, is there anything you would do differently? Anything you did that you didn't need to or something you wish you had done. 4. If anyone has used both a flat lid and domed lid, did you notice any difference in cooking times or fuel used due to larger volume? All answers are appreciated. And I may have more questions as I get farther into it.