We have a Orange spotted sleeper goby, and he is one of the most fun fish to watch. He also eats anything that we put in the tank ... flake, frozen, even pieces of nori. He does do a lot of sand moving, and he built a burrow under a large flat rock I have on the bottom.
Personally I love this fish, but he can be a bit messy. My tank is not heavily stocked with corals near the bottom, so he hasn't become a problem for them.