I've used two Lanolin based products. Lanox MX4 and Fluid Film. The Lanox seeemed to dry out too quickly. I just put the FF on and it is thicker, almost like thin honey, and seems like it might last longer as a result.
The lanolin based products are nice because they require very little prep, they soak/travel to areas you can't get to, environmentally friendly.
I put on van on a tarp to spray the FF, with a gun, and it didn't drip at all. FYI
It makes the whole undercarriage look wet and black, I can't imagine rust taking hold anywhere that is treated. I'm hoping for two winters out of one coat of FF.