It is fairly easy to make such a recommendation if you compare detectors to cars. Lets use a bounty hunter, an ATP and the equinox.
The BH is like a car with 2wheel drive. The ATP is like a 2WD car with traction control and the Equinox (multi-frequency) is like a 4WD car. Stable soils are much like driving any of these vehicles on a dry, paved street. Add a little mineralization and the analogy is like adding rain or light snow. The bounty hunter has a hard time gaining traction, but the ATP with ground balance and software to compensate can do a little better, kind of like a 2wd car with traction control.
Then a blizzard hits and there is a ton of snow. This is similar to hunting in heavy mineral deposits or conductive salt water. No matter how much traction control (software) you add to a 2wd car, (single frequency detector), it will never handle conditions like a 4wd car, (multi-frequency detector).
The ATPro has been a proven FAILURE time and time again in salt water beaches. Yes, I've owned them and YES, you can stretch the truth and say it works if you decrease the sensitivity enough so that it can hardly identify a soda can at 2". Meanwhile, multi-frequency machines typically work with the same performance in stable soils as they do unstable.
Well, I hope that helps you better understand why the Equinox isn't just another fad. Yes, it is a new detector, but it is a multi-frequency detector that is light weight, waterproof, and relatively cheap too. Its a trifecta that many detectors just can't hit...especially the ATP and AT-Maxx.