Thanks MH. After giving it some more thought, I like just staying focused on SLV versus branching off into DBB.
I created a relative price chart of $ALUM:$SILVER and it clearly shows silver outerperforming. I created a relative price chart of $COPPER:$SILVER and it looks promising but the long-term trend of that relative price appears to have topped in 2006.
I think DBB will definitely make money, but it looks like a coin toss whether it will be more profitable than SLV.