It is worth $330 new. Handy for working in tandem with your FEL if you need t move a lot of dirt or sand. Load both at the same time for long distance transport. For short distances, a box blade would probably be better and with the scarifiers, likely dig much better. It should dig ok in the Lake Livingston clay if the top link is adjusted correctly. I just depends on what you plan to do as to which implement is better.
I would think that if it doesn't work for your purposes, just relist it on Craigslist and get your money back.