>>3
As much as I hate JavaScript, there's no way you can make JS+SVG/Canvas/WebGL run slower on a modern browser than the fastest Flash ever did.
Oh, and in order for Flash to run acceptably, you need a half-decent
coder who can read a bit of documentation instead of copy-pasting crap, which is a losing strategy (as a concrete example, of the big sites for video playing only YouTube gets it even remotely right).