Hi,
Well, I did a little head to head finding a few small nuggets. I'd find them with the GMT, then check with the GMZ. This was stuff a few grains to less than a grain. In most cases, either due to the small size or the depth or both, the GMZ would not detect nuggets the GMT would.
But that is exactly what I'd expect. You are comparing a unit selling for under $500 to a unit selling over $700. If you want the best spend the bucks.
I think testing is more valid when limited to a price range. If you look at car comparisons, they compare at a certain price range. Comparing $20,000 cars with $30,000 cars usually just proves when you spend more you get more.
So really it is more a question on how does the GMZ compare to other nugget detectors with an MSRP under $500? The MSRP on the GMZ is $479.95. Since there are not any others, the GMZ wins hands down. The closest you can get is the Tesoro Vaquero for MSRP of $525. That would be a fun head-to-head comparison. Given that the Vaquero is lighter, offers more coils, and has full range discrimination and a theshold based all metal mode, the case can be made that the Vaquero offers the better value, as both can probably be had for about the same price after discounting. But as to how they would fare in a head-to-head comparison I can only guess at this time. I've used both, but not at the same time. My guess is they'd be pretty close.
Steve Herschbach