Has anybody tried the Sonax Nano system?
Yes. Is it any better than the "old" systems including Caurnaba ? Better in regards of ease of application, gloss and longevity.
You might try asking or searching in the Detailing and Showroom forum section: Detailing & Showroom - FerrariChat.com Most of the car care discussions take place in that section.
Fine as in just like most or as in better than most? The reason I am asking is that I have been recommended those products, but to get them I need to import them from the US. The usual stuff ( Mothers and similar) I can buy locally. Is it worth me importing?
For a spray sealant? Yes. Are there better over the counter options? Yes, but they come with caveats. For instance, Cquartz UK is far superior to any sealant. But it also requires much more effort and prep work for it to make sense. But in terms of what you could buy at a store, Sonax Polymer Netshield is superior. I hope this better answers your question.