I vote for it. With other tools I was used to do a little work in the UI, then going back to the xml code for detailing, and back again to the graphical notation for adding other activities to the process, ad infinitum.
Another thing I'd like to see is any kind of automatic displacement / resizing of processess, so that one shouldn't have to adjust the visual layout by hand only.
I'm very impressed for the good level reached by the tool in such a short amount of time, congratulations!
Regards