I know Collnite has some liquid waxes that are pretty durable, but other than that, I've heard incredible claims on durability from their past waxesl ike 476.
Meguiar's M16 also has had some great raves about its durability.
I would be very interested to find out more about
Souveran. I just ordered some and will be getting it next week, so we will see I guess.