to test NXT's longevity, I tried NXT on the hood of my dark blue 97 Explorer and then topped half with P21S. The untopped half lost it's beading and water sheeting qualities in no time. It's a solid all-in-one product. NXT has terrible longevity and is not a topper.
Unless....you plan on applying NXT every month.
I would recommend topping NXT with S100 for longevity. Then you can go a to a 3x per year full detail. Be sure to use a quality QD after every wash.
