Saw a chick one time lose her cookies 30 seconds after 2nd entry. Bad thing was she couldnt go 1 min afterwards without popping off again. Never saw a lady shiver that much, needless to say she only lasted 10 min max. She wasnt only girl trying this out, was at a Sw club, but she passed out just after and stayed out for over an hour. The remainder of the girls could go on for what seemed like days.
Best for this is a sex swing... not expensive but needs installed correctly. Once a chick experiences the swing they want it a couple times a week, but it take 2 dudes , and wife hasnt achieved it yet , but getting them both to blow at exact same time is on her wish list.