The DD will get you more targets in bad ground simply because you can now hear those targets you couldn't before. It does not go as deep as the mono loop in moderate ground. BUT, the Sierra Max coil also works better in bad ground than the smaller loop does. It sees more of ground when you balance it so you have more of the soil matrix balanced out. It is a little more stable and you definatly get more depth than either of the smaller loops, it finds targets almost as small.

Digger Bob