I bought all three of these when they were last on Woot. It was quite hard getting the items out of the plaster block, using the tool that was provided. The tool was very small and painful to use. I ended using a real chisel and real hammer to do it. It was also really messy.
But my 4 and a half y.o. kid loved it. Probably buying another set of three, again.
Why? Because both dino doo-doo and the look on my son's giggles when we find it, are priceless