I myself hate these kinds of tests. Air tests are as everybody knows pretty much worthless. In the ground tests I notice they eliminated the smallest target, which is the only target that really should have been used in that scenario. Also that ground seems pretty mild to say the least.
Note to anybody, individual or manufacturer, that wants to test a metal detector or especially compare 2 or more different detectors. Example: Go out into field with multiple units preferably with say 3 guys with different units to compare. Stay together and find targets in the raw. When a target is found, then check with the other machines and compare capability. Then dig the targets and determine at what depth and such. Do this in a known gold area with heavy mineralization to really test the machines capabilities. Use experienced detectorists with machines they are confident and capable with so if needed proper adjustments can be made. Also, and this is a biggie, use the same type and size of coils on all machines for a proper comparison.
I get tired of comparisons where one machine has a mono coil and the other a dd. Or maybe one detector has an elliptical and the other has a round. The real aggravation is when two completely different sized and type coils are used to compare. This type of evaluation just insults my intelligence.
I myself will take a real world evaluation from a guy like Steve H. any day over this type of example video which is doomed from the start for so many reasons. No offense intended, but lets get with the program. If you want to test metal detectors, do it in real world scenarios and compare apples to apples, not eggs to grapefruit. Dennis