We've been using Cocoon framework for years and are very happy with its simplicity and RAD features.
Although we use very old version of Cocoon (2.0.5), it still satisfies us.
Unfortunately there are some bugs inside those old framework libs that we cannot fix as well as some memory leaks
from libraries that are no longer in use. That's why we soon plan to upgrade to the newest release of Cocoon. 
And i have few questions related to that topic:

1. Is C3 stable enough to give it a try in a production ?

2. Is there any equivalent of XSP in C3 ?

The flexibility of XSP is very important to us in terms of introducing many new/short changes
very fast to our web application. We just make a change and that's all - cocoon engine recompiles the java-related
class and it is instantly available to us - no recompiling from our dev team, no deployment, no app server restart no fuss at all!
It allows us for very rapid changes! That's exactly the kind of flexibility we want to have in our dev environment.
And we were much worried when in next Cocoon releases the support for XSP was abandoned. As far as i know
XSP became deprecated in C2.1.11 to be totally removed in C2.2.x and i suppose in C3.
I didn't dig much into all the features of new Cocoon but it seems like in C2.1/2.2 the best thing to use on the "controller" side
is Flowscript code. We were hesitating to switch from pure Java controller code to Javascript/Flowscript
code because in my opinion the continuation mechanism is error-prone, yet the developer must take care of many intricacies
around session/continuation expire times and so on. But the main reason for us not to go for it was the language -
Javascript - NOT Java. Although if i get it right, you can just instantiate any Java object and get access to any Java library available
around from Javascript, it is not as much flexible as java was in XSP. Though it still doesn't require any recompiling!/redeployment phase
from  the dev team as i assume.
In C3 you can have Java controllers called and that is Good, but it does require recompiling the Java
class and redeploy it on the server (and restart app server?). So it will be much much SLOWER than just dynamic-recompiling by cocoon engine without any server restart.
So i wonder if there is any mechanism on the controller side available in C3 that enabled us to still use Java but doesn't require from us recompiling java code/making redeployment/restarting the application server ?

3. Is Flowscript using some separate javascript engine like V8 ? Is it run inside JVM as a dynamic language feature ?
Whats is a preferred method to be used as a logic controller in C3 - Flowscript or Java ?

4. We don't want to go yet with C3 alpha-3 because it still uses old Xerces and XML-API libs. We found out there are some issues with those old libs under Tomcat 7 while working with "bloated" XML namespaces or handling some SAX errors. They had led to some memory leaks in our environment.
I spotted on the changelog that you have just updated C3 beta to the newest Xerces/XML-APIs. Thank you very much for this. I really appreciate that important change. Can we have some light on when the beta is released ?