It mainly depends on how you understand each
framework and its implementation. Cairngorm is support by abobe so i suggest that you can go for cairngorm
It purely depends on your understanding and the requirements.
According to your requirement you can choose the framework.
Here is a link compares between different frameworks.
You can also find more blogs discussing about frameworks.
actually , I have the same question in pure asction script project .now I
am using puremvc framework ,I also heard about robotlegs, I am trying to
find a better one.