I've never owned or used the MXT so I cannot compare it to anything else. I did own a V3i, a MX5, and a MX Sport. I loved the V3i and the MX5. I liked the MX Sport. In their time I think all 3 machines were underappreciated performers.
I currently own the Legend, the Anfibio, the ORX, the Deus 1, the Equinox 800, the Vanquish 440, and the Garrett Apex. Well, I don't actually own the Vanquish - it is my wife's machine. I did own the Deeptech Vista X - and very much regret selling it.
For the most part my soil is fairly mild. I much prefer hunting in old sites where iron bits and pieces abound. I prefer smaller coils. I do occasionally hunt the beach (salt water).
All of my current machines have a faster recovery than the Whites machines I did own. Of the Whites machines I did own, the MX5 was the lightest weight. With the exception of the Anfibio, all of my current machines are lighter weight than even the MX5. My guess would be that all of my current machines - with the possible exception of the Apex - are deeper than the Whites machines I did own. I can't be sure about that; it's just my gut feeling.
If your soil is mineralized and/or you hunt saltwater, a multi-frequency machine will provide you with numerous advantages (depth being one, stability being another).
My thoughts on my current machines.
Nokta Legend - If I could keep only 1 of my machines it would be the Legend. I believe it is the most capable (overall) of the machines I currently own. Outstanding build quality. Stock wireless headphones are very good. Excellent (recovery) performance in the iron littered sites I prefer, and in areas with modern trash. Great depth. Great on the saltwater beaches to. Lots of adjustment capability. For me the menu icons are too small (I need glasses to see them). The keypad buttons are difficult to see as well (easily fixed with a white paint pen).
Nokta Anfibio - Great depth. Very good recovery. Outstanding build quality (it is a tank). Lots of adjustment capability. Stock headphones are good (not as good as those for the Legend). Just OK on the saltwater beach. Very good to great elsewhere. I thought the menu was confusing when I first got the machine. (I am used to it now - and it is fine)
Minelab Equinox 800 - Very capable machine. Very good in almost all hunting situations. Deep and fast. I do like the menu - well thought out and easy to use. Lots of adjustment capability. Headphones are good. Suspect build quality. I think the Legend is the better machine (performance, build, and cost).
Minelab Vanquish 440 - Very simple machine. Easy to use and the menu is good. Limited adjustment capability. Did not come with wireless headphones. Build quality is good. Performance is good - especially for the price. I think it is a very good park machine. Of my current machines, this would be the one I'd sell first. It just isn't my cup of tea. My wife chose it because "it is pretty."
Garrett Apex - For me this is the most fun to use machine. Very simple to operate. Limited adjustments. Very good build quality. Best wireless headphones I've ever used. Love the screen. Doesn't seem to be as deep as my other machines. It down-averages when a good target is near iron (the VDI number won't be as high as it "should" be) (listen for the high tone mixed in with the iron grunts). Very good on saltwater beaches. I find it very good in the iron - if you ignore the VDI and dig the high tones.
XP Deus 1 - Excellent recovery speed. Very good depth. Very good build quality. Very light weight - super easy to swing all day. Great in iron. Wireless headphones are good, but some find them uncomfortable (I like them). Lots of adjustment options. Super easy to change coils. Charging clip (for the coil) sucks. Charging three things (remote, coil, headphones) can be annoying. VDI bounces around a lot on targets that are a bit deeper (dig by tones). Coils are very expensive.
XP ORX - Really fun machine. Easy to use. Very light weight. Excellent recovery speed. Very good depth. Very good build quality. Very light weight - super easy to swing all day. Wireless headphones are good, but some find them uncomfortable (I like them). More limited adjustment options. Super easy to change coils. Charging clip (for the coils) sucks. Charging three things (remote, coil, headphones) can be annoying. VDI bounces around a lot on targets that are a bit deeper (dig by tones). Coils are very expensive. Great in iron. Modern trash (aluminum bits and pieces) requires you to watch the VDI numbers if you wish to limit digging pull tabs and the like. Only 3 tones and you cannot adjust the tone breaks (the biggest weakness of the machine).
Deeptech Vista X - Excellent recovery speed. Very deep. Good build quality. Light weight - easy to swing. Two discrimination discs - very precise settings are capable, allowing the user to cherry pick if they wish. Two-tone machine (ferrous/non ferrous). Very descriptive audio. No screen. Adjustments are by knob and nearly infinite. Has iron audio volume. Very easy to use. Does not come with headphones. Wireless headphones would require a transmitter. Runs on 8 AA batteries.