Overall, I think its a pretty decent site. All the games I've played (Bob the Robber, Space is Key, Fireboy and Watergirl, Run 3, etc.) have clear controls and usually work unless I have bad internet. The only problem is that many of them don't have much to do with math, if anything, so the title is a bit misleading.
Tip for consumers: Would recommend
Products used: Fireboy and Watergirl in the Forest, Light, Ice, and Crystal Temples as well as Fireboy and Watergirl: Elements, Fireboy and Watergirl: Fairy Tales, Run, Run 3, Tiny Fishing, Bob the Robber, and all Space is Key games.