Glad to see a couple people here have tried Duragloss - been my best sealant for years now. I have yet to try Zaino - sounds promising. I liked what I saw with NXT, but didn't do a controlled test to accurately judge longevity, but I do recommend it to my neighbors. Wasn't overly impressed with Klasse - didn't match the gloss depth of Duragloss. Paid $$$ for the Pinnacle waxes - nice result after your done, but already loosing color depth after 2 weeks.
My next test this Spring will be the new synthetic sealant from Richard Griot - he was never a fan of polymers until last year. His other carnuba based products are very good, but I'll admit my bias that I am not a great fan of them *carnuba) due to their short protection duration, especially in the more southern climate of NC. Anyway, I was told his new polymer has the color enhancement capability of the waxes with the durability of the polymers - we'll see!