Johnny, it would be no better for caches, than any standard detector, or two-box detector, etc... ANY detector can tell you "there's a large object here" (jar, box, etc...) simply by giving you a large beep. Right? So why does a "mess of pixels" tell you anything different? You seem to think there's going to be this magical picture of a mason jar, or box with a pad-lock on it, etc.... It's not gonna work like that. A chunk of cast iron cr*p, a hubcap, an aluminum can, etc.... are all gonna be a mess of pixels. How is that any more helpful than a detector which beeps, and tells you the same thing: "there's metal here". Simply get a 2-box unit, and you won't pick up anything smaller than a soda can, to begin with, if you're thinking there's a cache somewhere.
As for the rings in their ad, I'll tell ya what: You go buy one of those machines, take it out to the nearest urban blighted inner city park, and go see how many gold rings you can effortlessly dig up, while leaving tabs, foil wads, etc... in the ground. I think you're in for a rude awakening. And sure, of course they'll show pix of gold rings in their ads. We've seen this for decades now, in every single advertising ad for regular detectors too. You know the drill: Whites, Garret, Fisher, etc... will all have pix and testimonials, of their poster boys standing their holding their latest gold ring, or a jar of coins, etc.... Heck, an XLT even has an icon-pix of a ring on their screen too, when you wave a gold ring in front of it. And a little "quarter" pix when you wave a quarter, etc..... I have serious doubts that what you see in that ad (the glowing ring shaped image) is going to be what you're seeing in the field. For example, what image would a tab make? a foil wad? A singular coin? etc.... Notice their ad doesn't show any of that, as it's probably all the same thing.