I think that I have been a WebWonder user for nearly 3 years. I can definitely recommend it to anyone think about creating a website but frightened of the detailed work involved. WebWonder makes it all easy, allowing you to concentrate on what you want rather than how to do it. My site has grow from nothing to ove 180MB and is steadily growing, and all written in WebWonder although my use is a bit more sophisticated these days.
I find image processing a delight, I have lots of thumbnails almost all generated within Webwonder, because I want the basic pages to load quickly whatever your internet connection and allow the user to decide which pictures to see full size. I have both software and documents in the site and depending on the browser they can all be downloaded or displayed, just by linking to them.
The only real problems I have encountered is WebWonders love of adding   at every opportunity which sometimes have to be editted out manually (I use !Edit) and the occasional abort when editting larege pages usually cured by exporting and importing the page for some reason (I discovered this when trying to save a concise example that consistently failed to send to David Snell for debugging. once editted it refused to fail!
The only real improvement I would like to see is a typo checker, to catch the many typos I leave behind in spite of proof reading, I think I have dyslexic fingers in one hand.