It’s strange, very strange, when the manufacturer has to prove that its new machine is on par with an old one. But it’s difficult to prove it if the new detector looks and works similarly to the old one. For example, the manufacturer says that the new Garrett AT MAX provides greater detection depth than the old Garrett AT PRO. But is it true? Both devices actually come with identical coils. Or, as another example, according to Garrett, on salt beach (and in saltwater) will the Garrett AT MAX operate considerably better than the Garrett AT PRO. Here’s a salt beach test: to compare the Garrett AT MAX and Garrett AT PRO. Also, a depth test: how the machines react to salt sand and water.
All about the new Garrett AT MAX is collected here (news, different tests, comparisons with other detectors, first reviews). Plus, on Knowledgebase pages there is additional info on this machine (specs, features, the list of coils, all you need to know before buying this device, important clarifications).