I have used both and another very good product Supertrol 001
http://www.actioncan.com/type/509/Supertrol-001-Anti-Rust-Fluid
I find two differing properties are needed, one a penetrating one that seeks out every crevice and gap in spot-welded assemblies and a more tenacious one for exposed surfaces where prone to being washed and worn away. So I treat with the former then the latter where I think it is needed, I believe it is the product that seeps into the areas where the paint never could that gives the more valuable protection, Here Supertrol 001 is very good indeed , but in the Dinitrol range they used to have a similar product.
Waxoyl is okay for exposed surfaces where it leaves a reasonably tenacious film, but it is poor at the creeping process. As it cools it becomes far too readily too viscous to creep anywhere and cold its a waste of time IMO.
It is a lot of years since I last used products from Dinitrol, basically because of availability but I found them very good. I specified Supertrol treatment for the products the company I worked for produced so was able to piggy-back a private bulk order that way at prices I could not obtain retail for the other contenders so by far my greatest experience is with that. And it is excellent.