Clarification of APEX Listener + (WebLogic or GlassFish) for Production Support

We've been using APEX Listener in Dev and Staging environments in a completely stand alone fashion. So far, it does everything we could want and I suspect there are still a lot more cool capabilities of which we are unaware.

We want to use this for our production implementation but, there is one sentence in the Installation Guide prevents us from doing this:

     "Standalone mode is suitable for development use only, and is not supported for use in production deployments"

Can anyone on the forum explain, specifically, what new capabilities we will gain by installing the listener within a WebLogic or GlassFish container? At 30-40K, I need to be able to justify this expense. I don't think I will get very fay if I say that we get nothing for our investment except that Oracle will provide support.

What, specifically, is it about being within a WebLogic or GlassFish container that makes it so much more "production worthy" or "supportable"?

Thanks for you thoughts,

-Joe