I used lump in my UDS for the first time this past weekend. With one vent open, I couldn't get it lower than 300. Had I not watched carefully, I would have ruined a rack of spares!
When I use briquets, I get a clean 230 with one vent open. Starting with about 10-15 lit briquets, and a full basket of unlit. Briquets work the best.
Green OTG; Black OTS; UDS; mini-WSM; Weber Genesis Silver; USMC 86-94