My Take
The site is fun and interactive with a ton of game for every grade level and math subject. The site does have ads though, which may become a problem for interactivity if the student or computer does not have an adblock software. Other than that I think the site is great and could be used by everyone.
How I Use It
I would allow my students to explore the site and play the math games that they would like freely at home. Then we would do in class activities with certain games that I believe fit best for the lesson plan.