It doesn't leak at night as pads do, it's cheap and environmentally friendly, but mainly that it doesn't dry out my mucus membranes and doesn't contain bleach and pesticides that I don't want anywhere near my uterus.
Congratulations on your 3 year anniversary! I recently started using a menstrual cup and the only thing that I'm sad about is that I didn't start with this sooner. It's amazingly great in every way!
You have saved my life... never again will I use tampons that destroy my mucus membranes and it's effects that destroy my everyday life. The menstrual cup is the best thing that ever happened to me! You are a gift of life to us women!