To be honest, having used both over a period of 40 years they both have their plus and minus points, but actually share more features between them than differences. I chose Waxoyl this last time because of availability. Dinitrol is not always easy to get hold of.
I've recently used the Bilt Hamber wax and found it to be excellent.
However, whichever product you use the deciding factors will always be good preparation and thorough application. They are not miracle cures and if you don't spend time and effort ensuring the surface is free from dirt and loose rust/ try to save a bit of money by thinning it down too much or spraying too thinly then whatever you choose won't be adequate.