Anyone here ever used Corroseal or other rust converters/protectants on their car's undercarriage, brake components, engine parts (manifold, for example), etc.? Those products are pricey, but a lot of people swear by them. I, however, am still unsure. Will my car wipe out my credit cards if I coat the bottom in magnetite? Will it erase all my Flock of Seagulls tapes?