.........that by "Beach Hunting" you are speaking of salt water beaches.
I'm retired, live a mere 10-15 minutes from the nearest beach and have been using a a CZ 7A Pro since they first came out. It has since been superceded by the CZ 70 which is identical save for the additional tone and the cosmetic change of "Square Tab" to "Relic"....... which buys me nothing in my application.
Although primarily a beach detectorist, I do a fair amount of detecting in the parks/schools environment where it excels.
The subject CZs are very easy to learn and use, exceed the detection depth of the XLT, are hotter on nickles, have a "SALT" mode, some weather-proofing and come with a lifetime warranty if purchased new. The fact that Fisher has enough confidence in their product to offer such a warranty implies that chances of you having problems when purchasing a used unit are rather slim.
Reports on the 3D performance indicate it's great in the specialized circumstance for which it is intended, but offers no advantage on the beaches and in the newly developed parks and schools in which I detect.
My recomendation? Go with the CZ 70 if buying new, but give some consideration to the CZ 7A Pro if buying used.
Hope that helps.
Chet