I;m uncut, but i gotta say the best one i have used is a Eczema treatment creme called dermeze, just 50% Parrafin liquid and 50% white soft parrafin (vaselene) its like vaso, but flows more, it melts at 30 degree's so if you get a bit of friction going it just melts into a slipperly liquid. plus afterwards your cock is really smooth. duno about availablitlity in the US of A, but it's made by the royal childrens hospital in Melbourne. brilliant stuff.
Just, because it's made from paraffin, it's very flamable.. so not best to smoke and wank