I think it's improved alot over the years. The features nowadays are way more robust, yet it's still as simple as ever to use. Take a look at what I made with a few dedicated minutes of my time. Tell me what you think. I plan to use it as a promotional piece.
I have used Wix in the past. Pretty "neat" and all, but when you hit a wix site, you know right away. They are flash based, which is why there's all the nifty animated stuff. However, the sites take forever to load, and if you don't have a fast computer, the latest flash players, etc., wix.com is a bad experience. (in my opinion.)
Plus, idevices do not support flash, that's a huge loss right there.
For minor things, such as advertisement like you say, may actually be a good idea. I wouldn't use it for a main host though, personally.