I scored "awesome", passed all tests. Except the WGT meter.
I see that lied above, I actually never passed the "Ultra test". Interesting, in ways, is that Chrome, with Pepperflash, seem to be very good. It scored less than Opera and Firefox, but that seem to be because it apparently caps the fps at 60. It performs much better than the others on "heavy" and "ultra"
In WGT, for me, the meter is smoothest by far with Chrome. Unfortunately I can not use it since it react very poorly to my click.