I’ve been using it for 4 years on 4 different vehicles. In my opinion it’s the best choice for newer vehicles or ones with less rust. My 2012 Pilot imported from Florida had almost no rust. Its well preserved with 2 coats. No maintenance required in the past 2 winters. Any surface rust completely stopped. It’s maintenance free and it stays clean underneath. The 2006 Escalade had more rust. Frame is good, needs a small spray here and there. I would not say it’s progressing, but it does bleed red occasionally in a couple areas. Worse off are the Nissans. They had significant rust to begin with. They keep requiring respray especially in the seams. The 03 Maxima just got the black version. Mainly to hide the rust better. For now it looks good. I’m sure next summer it will be bleeding from somewhere. I think its a little too thick to penetrate deep rust enough to choke it off. Definitely slows it down. I think when it gets to the point that you have chips, you’re better off with thinner visc oil spray for better penetration. I do have an oil sprayed car in the family. Similar to cosmoline it has some bleeding in the splash zones. Need to touch them up every few months. Then spray the whole undercarriage before every winter. Oil sprays are messy and require constant maintenance. Cosmoline is a lot less maintenance. A lot less mess. But it’s performances not as good on heavy rust as oil. Hope that makes sense.