Newbie questions

I'm evaluating XUL/RDF for a new ERP app or better to port an existing
app.
In the last weeks I've gone through the tutorial and googled
everything with XUL/RDF but I still miss something.
I hope this is the right place to post if not please forgive me and
point me to the right group.

1. I need a remote app without any local storage, is it a viable
solution for a complex ERP app in XUL?

2. Is it correct if I say that the "life-cycle" of a XUL app can be:
SQL->RDF, XUL widgets change the RDF in-memory, RDF will be serialized
and sent to a remote app using XMLHttpRequest, RDF->SQL?

best regards,
Lorenzo Fiorini