I was going pretty much every night, about 5 times per week. I stayed in there until I couldn't handle the heat anymore, it definitely felt beneficial. I want to continue going but I've just moved house away from it.
It seemed to force the lips to peel neatly and effortlessly. After each time the amount of skin coming off was getting less and less. But obviously this is probably because of everything else I was doing/not doing as well.