menstrual cup??

Okay, so my friend was telling me about a menstrual cup. She said it was super convenient and extremely comfortable
I researched it & it seems like it would benefit me greatly during the school day and during sports. But in kind of skeptical that it holds it there all day & you can reuse it without having to do anything. 
Any advice or comments on what to do or how to help? It would help me a lot !