Lower your stem as much as you can. If you don't see yourself staying in that position for very long then drops won't necessarily do anything for you. Mustache bars already give you the decent hand position similar to drops.
However I will say that I like the new short reach shallow drop bars that have been out for a while. The vintage bikes I rode for so long had drops with a huge amount of drop. Also, if you don't have STI's on those mustache bars, then you'll probably find the move to drops a little expensive due to the cost of STI's or dual control levers.