I switched to syn wax on my black Cayenne and love it. Carnauba is traditional, but takes a lot of effort (and time) with the result that I put off doing it. The liquid syns go on and polish out so easy...like you're just wiping it down. I don't see it as a big chore. And it lasts as long as carnauba for me. I doubt one is safer than the other, except less buffing with syn wax means less swirls in the paint. I'm using Einzett Glanz Wax, but there are so many brands to choose from...and lotsa hype and vanity pricing. I've read a lot of good stuff about Turtle Wax Ice.