I have used Zaino in the past, and like it very much............... mainly on light colors, as it gives good clarity and reflectivity that enhances light colors. Zaino is also tough to beat when it comes to durability.
However, there are now many good sealants on the market that weren't around when I started using Zaino. Products like UPP, EX-P, WG, NXT, are also very good products.
As for the comparison testing................. the only test that matters is the one YOU do!
Good luck with whatever you decide.