10" elliptical DD vs 8.5 DD

[sling]

So as i said before I am satisfied with my oval 10DD because it really sensitive for small items( as it post to be) but now i think
the 8.5 also catch the smallest coins that exists but even deeper.Coins are never as small as gold nuggets so the sensitivity of the 8.5 might be enough
to coinshooting.So the 10dd is little more sensitive but the 8.5 is little deeper.Do you agree?
So before i buy the 8.5dd please talk me out of it or into it!

 

[Canewrap]

I doubt that the 8.5 is deeper. If you're working in moderate to bad ground (where the DD coils are most useful) the DD coils usually get about the same depth as the concentric, which is to say if its an 8.5" coil it gets about 7-9" deep and the 10" eliptical should get about 9-10" deep (that is in moderate ground, bad ground is a little less). Of course your depth may vary, depending on conditions and this is according to my experience. I would get good usage out of the 10" eliptical and not sweat it, the difference in size is not enough to warrant changing it out. If you don't have a small coil, like a 6", for hunting in trash, you'd be best served buying one of those.

 

[sling]

Jackpine Savage said he was more satisfied with the 8.5 DD.no im mixed.
if the depth different is minimal i dont think it make sens to buy the 8.5DD because the 10" really comfortable to use:
cover lot of ground and between corn is the best because only 5" wide and plus bite the tiny coins as angry dog.
If the 8.5 would be deeper more than 10% i will think about it.But if not for what?
So can anyone state that i will get 1 inch more with the 8.5????
If someone has both just make an airtest please!