animations (css) slower and choppy under Maverick Safari 7

Updating to Maverick with my iMac using Safari 7 I noticed at once that my animations created with Edge have got worse. Slower and little choppy. They perform instead very smooth on Google and even Firefox (which usually is less good with css transitions). Has anyone made the same observation?

In part I could better things a little by adding

#workPage div {

          -webkit-backface-visibility: hidden;

}

to my css. workPage is where the stage is placed.

Much better with this but the problem is not entirely solved.

What is this slow css transtion thing with Safari 7?

I noticed that it bevaves worse also with css transitions that are done manually (not with Edge)

Anyone of the team that treated with problems under Safari 7?

PS I am using an older version of Edge (1.0.0.18521541)  though. Did I miss something?

Thanks for help

Garavani