I have used Optimum No Rinse before. It works pretty good for low to medium level cleaning. I usually fill a pump sprayer with the solution at wash dilution and liberally spray the surface before wiping with a microfiber "muppet head" mitt in a wash bucket with ONR solution going panel by panel. The bucket only wash does cause some light marring in my experience. If your car is very dirty, I would not use ONR washing.
Chemical Guys out in SoCal has a Eco Wash wash system which looks decent. I have no experience with it though. Looks interesting.