I have used beta 2, didn't like it, uninstalled it and now trying beta 3 again. Get it here if you want.
Firstly you have to remove older beta version before trying this one. It's a big download so you'll have more than enough time for a coffee or two.
It appears to be a bit faster, better display (e.g. my site here, color is still a bit blurred on the sidebar) but overall there are improvements.