I just tried it out. So far it's working okay. I had a little trouble when installing because I forgot to log in before going to dev/build. The missing tables caused errors that made the website unreachable (even the log in page), but this probably isn't a Simple Wiki problem.
I have a few issues with TinyMCE. Firstly, it won't fit into my website's layout. I have a fixed width layout, and its toolbar disappears over the edge. Next, when clicking on insert image, it opens a window with a completely broken image selection control. Is there a method of customizing it for the wiki frontend?
I would try out the other editor except, as you said, it doesn't have a decent tables plugin (it has one, but it's pretty dismal).
It would be useful to me if I could disable inserting and deleting of pages from the front end on a page by page basis. Usually a wiki editor should be able to add pages, but sometimes editors should only be able to edit the one page.