Ultimate Undercoating Argument Thread

We all know our own opinion is the right one, and everyone else is wrong!
Just like we all know how Royal Purple is the only good engine oil, Red Line makes the best diff fluid, K02s are the best wet-traction tire, etc.

This thread is your chance to share why your grandma's bar chain oil + diesel mix is the ONLY good undercoating solution! So, which undercoating do you use, and why are you right? You're only allowed to share correct opinions here. And if you don't live in a salt state, we don't wanna hear about your unrusty life.

*i hope the sarcasm is clear^ but I do think it can be helpful for folks to see various options, hear personal experiences, and get opinions*

 

Who told you about my nana’s undercoating recipe?

 

I use Surface Shield because I'm gullible and I got conned into it by a Youtuber.

 

Papaw's mouth doesn't stop running after a few drinks at the American Legion!