Actually, I had Invisalign and I give it two thumbs up
It did quite a change with my smile. The one thing that I didn't realize though, when I got them was that they say that they're not noticeable, but what they have to do is make notches on your teeth using filling material in order to give the trays some leverage to move the teeth around. Pretty much they give you the trays to use and change every two weeks, then they'll have you go in and shave some space from between your teeth to make room for them to move. They're beautiful for being able to take off when you want and it's not painful. Sometimes after you change a tray, your teeth might get a little sore, but it's really nothing.