Good friend of mine is a bodyman with about 25 yrs experience. He says they are a joke. He does swear by the "paintless dent remover" process taht is done professionally....Guys that drive up with funny little tools and in about an hour they can pretty much fix a car hit by hail with several dents! Costs about $100 depending on qty/size of dents.

SINK PLUNGER...!!!