I jsut recently got a Deuce and have been wondering this myself. Right off the bat I'm going to tell you that a pre-amp combo from Doug's will warm things up. People here have posted this and I know that they were good in my Recto. For a bit more low-end, either EL34L or possibly KT77 power tubes. I'm not really familiar with Down's sound, but for Godsmack covers I always turn on my EQ (V-shape). I use it to bring out more lows and a scooped mid sound to give it that Recto sound that is inherent in a lot of nu-metal tones.