Prior to using the NXT on a wet car I used the Meguiars Spray Wax although this product was designed to use on a wet car. The spray wax results were OK at best but protection was poor even after the first rain.
If you do decide to use this method I would recommend applying it with a microfiber cloth and changing the surface of the cloth frequently to avoid swirls. You will also end up using a great deal more product as the microfiber will soak most of it. I used the NXT because it's easy to apply and remove and the synthetic/liquid formula allows it to spread easily on a wet car. Living in Maine I'm getting creative with my detailing techniques