How complete is the javascript API?

Hi,

I am trying to serealize a AI document using the javascript API. Based on the "AI CC SCRIPTING REFERENCE" I assumed this could be done by simple traversing the dom and saving the type and properties of each object. It seems however that the API isn't complete. For example, I can't figure out how to read the transformation matrix of a symbolItem. (i.e. when creating a new symbolItem from a symbol and then resizing/rotating/repositioning it, how can I find these new properties?)

This is just one thing I ran into, that might be fixed using the C SDK. I am wondering however if this is worth the effort or more like filling a bucket full of holes? How complete is the javascript API?

Thanks,

Tom