Well, I think I can tell that I've made a little funny accessoire with a few other girls from Flight School. We cut off the first 10 inches of a tape measure, then we colored the first 5 inches of it red, then from 5 to 8 yellow, and 8 to 10 we colored it green, so we could immediately check whether a guy was a "unrestricted-go", a "gotta work to satisfy" or a "take care of another girl" man. However, that tape was more a self-made sex toy, not a real decision finder.
The thing that made it really sexy for the guys who liked this kind of play was that I espoused a very cool, clinical way of measuring, like I was a doctor at the physical fitness test. And another thing had to be considered: I never used it on a guy who would have been in the red zone. That could have had devastating effects on whatever erection he had :redface: