PB blaster has more detergents and seems to eat rust better,
I dont use wd-40 for anything but metal cutting, threading, and/ or parts assembly,
I use jig-a-loo to kill ants (seriously it works) I have used it for everything I would rate it one step below pb blaster as a penitrant spray, there is not one thing you can't use it for (well don't eat it or breathe it) , it contains methylene chloride the banned industrial solvent, that stuff messes you up if you breathe the fumes in