I have owned two, my current one is not reef safe. Loves to nip everything. My previous one was SPS safe but clam and LPS unsafe.
As tony said, it's more to do with the individual fish rather than the type of fish in many cases. I have a Regal tang that is starting to develop a taste for clams. Plus, now that my Purple Tang has seen my Regal Tang nip at clams my Purple Tang is starting to get in on the clam nipping action
Most people would consider both fish reef safe :-)