Something doesn't sound right. You say that's the same results as the sunray 8" compared the minelab 10.5", your right and I would expand to say it would be IDIOTIC to use the 10.5" over the minelab 8" if the depth results were identical considering the added 2"s of coverage is only a nominal gain. I would gladly give up those 2"s of coverage if it meant less joint damage(elbow, rist).
My guess is that minelab uses the same coil cable on both the 8" and the 10" so testing not done I would say the 10.5" minelab gets deeper than the 8" minelab. I just can't except the idea that minelab would send out an 8" and a 10" coil having the same depth capability.
I tried out the sunray 8" and the way it balances out the XS is incredible. I wonder if the minelab coil will still give the XS the same overall balance.
One thing is for sure, it's just a matter of time before the Sunray 8" and the Minelab 8" coils are tested for depth by enough hunters to know positively the facts, and my guess is the reports will be coming in sooner than later.
GL/HH