I gave this a try two years ago. When I saw it on GAOTD I did what J-Mac did, passed then went back and downloaded it. Like all (writing) programs it has its strengths and weaknesses. What it always comes down to is my personal likes and dislikes. In Liquid Story Binder I like the Timeline. I like being able to enter notes right into the body of the book by simply typing in two consecutive periods and then entering whatever comment I want to make. The note text appears in a different font and color so it's easily distinguishable from the rest of the text and it's ignored when printing or using the word count. Another thing I appreciate is the Automatic Revisions Marker. The Repetition Visualizer is a great tool and there is a Word Usage tool that "allows you to view individual word instances sorted alphabetically."
I could make a great long list of nice features Liquid Story Binder offers. I can also say it's a bit disorienting and there are many parts I do not yet understand and some that I find useless or redundant. There are also a few little glitches. However, I believe that the program was intended to be highly versatile so it would be useful to everyone, regardless of how they work. If that is the case, Black Oblelisk has hit the mark.
I use PowerWriter for any serious writing and will continue to do so. I wouldn't (right now) trade it for anything, but I am finding more and more use for Liquid Story Binder as an adjunct and I've only had it a few weeks. The company is enthusiastic about their product and constantly making improvements so, even though the GAOTD time limit has passed, if you do any writing and have the opportunity to get it at a good price, grab it. Just be prepared to give it a fair trial.