I use the Sparrow framework and find it to mimic the Flash's API more closely, and the API as a whole is less complex. The primary downside at this time is that

I use the Sparrow framework and find it to mimic the Flash's API more closely, and the API as a whole is less complex. The primary downside at this time is that the community is less active/developed, but the author is very helpful when it comes to answering questions.