Have any girls ever tried using the Today sponge? What I've read about it sounds fantastic (can put it in hours before sex, don't have to change it no matter how many times you have sex, neither can feel it, etc.), but I also hear that the pregnancy prevention rating is something like 90%...or rather, 9 out of 100 women will get pregnant with perfect usage. That frightens me more than a little. But I think it'd be great to not have the guy have to deal with condom after condom, or to have to get on birth control... Anyone?