PureMVC - an Application Framework

I was introduced to PureMVC a few weeks ago through assertTrue's first rate video cast covering various Flex application frameworks including Cairngorm, MVCS, and others including my favorite, none of the above. But, PureMVC has many intriguing features, including...

• great documentation--the best I've seen short of having to buy a bulky book from amazon
  
• great use of standard patterns
  
• good use of publish/subscribe event model for loose coupling
• promoted as lightweight, but feels like a java framework

So as a java engineer it does feel lightweight, especially after working with spring, hibernate and j2EE--but after working with rails for the past two years, I still feel like it's a bit heavy. But for someone looking for the best framework for Flex applications, PureMVC gets my vote.

So why do I prefer none of the above? Well I'm not completely convinced, but I have a feeling that when a project gets to a usable size, the amount of registration for each command and value object would be overwelming. I also am more familiar with logic inside the controller as opposed to inside discrete mediators.