You know, I don't see how the D2 could go deeper in heavy mineralization ground if all it does is false in it? I thought I read that it was good in light to med mineralization ground somewhere but could be wrong. After using both at the beach I would have to say that the 950 concentric seems to go a bit deeper and like I said a whole bunch more stable which also seems to support my thoughts that the D2 is not the best choice for heavy mineralization like a salt, wet beach. And again the D2 will work at the beach but you will need to turn down the settings quite a bit to quiet it down and in doing so lose depth. Now the concentric will only have a very narrow point at it's deepest detection depth compared to the D2 as the concentric's detection pattern is cone shaped. That's one thing nice about the D2, you don't have to overlap as closely to get the same coverage. I'd be interested in others thoughts on this too.