I think it's cool to have many different things in a tank if possible. Snails are interesting to watch, but yes, can get out of hand. If you don't mind many of them, cool. If you want to have snails but get tired of having so many, I'd suggest nerite snails. They don't get very big and come in different colours/patterns. As far as I have been able to research, they don't usually breed in aquariums (or maybe not at all). I know I love mine, which is why I keep suggesting them.