All I have to say to this is oh my word. Haha. My boyfriend started me off with the one a size down from this and it was too small. It kept coming out which was a literal pain in the butt. So finally he got me this one. It is definitely bigger and stays in better but the hardest part is getting it in by myself. Other than that I love it but anyone who is trying to train themselves should probably start off small and work their way up.