The reason most people think they are similar is because Dan Duchane once compared them to each other, and the myth just stuck. Deca is a 19 nor which is way different than any other compound, actually EQ was made by accident, and EQ is almost identical in nature to Dbol, but the 17aa bond creates drastic differences once in the body. Deca does very little to help joints IMO, way overated. If you have sore joints just use Adequan and that will take care of the problem, not mask the pain. I personally am not crazy about deca anymore, I do like EQ though, actally one of my favorite AAS....