Good question. Unfortunately I don't really know, but BBSW management indicated that they didn't even consider EPNY to be close to the same league. He would have had more credibility had he not said their products are more along the lines of SEBL.
There is a guy on the BBSW board; memorybroker, who is fairly knowledgeable. He might be able to help, if you won't get bothered by the fact he is long BBSW.
Always nice to see an intelligent question and of course there is no response.