MapZone's node-based approach is pretty powerful (and a fine tool, especially at the price-). Probably it's biggest shortcoming is a good set of truly introductory tutorials to get users up-and-running. Even their 'learning' materials look intimidating as all heck when initially viewed. It wasn't until I took a long, focused, sit-down session with the editor that I even began to get a feel for how to work with the materials, and I still feel like a newbie. Really like it though.
rj