..it seems too obvious a piece of equipment not to have around.  Although once you've reached the point where the guy wants to pop, but it's just not happening, it's kind of too late, isn't it?  That stuff usually takes an hour or so to work its magic.

Unless the client asks up front if the provider has some Vitamin V, it's not all that useful.

Speaking from my own experience (and I know there's no way around this--just a fact of life), any problems I've had with a provider in this area are usually because of the need for condoms.  The sensation cut-down is just enough to make things difficult.  Female condoms make things a little better--but they're really only useful in certain positions (try doing doggie standing up sometime with a female condom--it's basically impossible).

Amazing that there has been no real improvement in the condom industry in thousands of years.  Anybody who can "build a better mousetrap" will become immeasurably wealthy--and will have earned every penny.