Reading this subthread I'm imagining the slow-mo of a bullet hitting ballistics gel coated/covered with $generic_amazing_bulletproof_coating, the impact, and the ripple effect.

I can't help but wonder if something coated with something perfectly bulletproof might actually make things worse depending on the bullet's angle - for example, under ideal circumstances, a bullet could enter and leave and take out some fat - but if everything's covered, the whole surrounding area is going to get some serious bruising instead.

Possibly. </Armchair commentary>