http://blog.greensock.com/tweening-speed-test/

I validated both of them and they are similar relative results on my machines. Try wiring your kits into these test units and see what you get for your own animation kit.

Also, in both benchmarks TweenLite and Go the authors of the kits their code came out the fastests in both cases. But they do offer the downloads and you can try them for yourself. The kits are all good in different ways and some perform better than others in certain profiles. So benchmarks are very important for relative measures and exhaustive stress testing, but that is one element to design. Simplicity, ease of use, completeness, purpose, whether it is for one big file ro many many assets etc. There are lots of factors to deciding what kit to use for what. I have some notes on this and am going to post soon regarding this based on about 1.5 years of work with as3 so far professionally and personal contract work and hobby. I have found I like to use certain kits in certain situations. Speed is very important though, most flash is client side so it is not as much a stress on the server but the more cycles you can save to focus on your main elements is always money.