Interestingly enough, I had a problem with ChartJS that no one seemed to be able to remedy. It was quite bizarre and at first seemed to be a cross browser issue, but after further investigation it seemed to just be some type of strange cross-machine issue. See it here http://stackoverflow.com/questions/30063762/side-effects-fro...
Given that, I had to do some hacky stuff upon every refresh. Instead of using destroy() on the canvas, I had to remove the Canvas DOM object itself, building it back up, and inserting it again. Because of this I am a bit skeptical about using ChartJS again, which is unfortunate because I do love their Charts. I feel like maybe SVG might be the better way to go for analytics.