Korean Investor-State Provisions: Sometimes Controversial, Sometimes Not

As I've mentioned before, investor-state provisions in the KORUS FTA remain controversial.  But it seems that investor-state is not a problem in other contexts:

Five years of negotiations on a bilateral investment treaty among Korea, China and Japan will be concluded at the 13th round of talks in Tokyo Tuesday. The agreement covers protection of intellectual property rights and liberalization of investment. ...   The investor-state dispute system, a highly disputed point in the Korea-U.S. free trade talks, has been included in the new treaty since the parties had no significant differences in positions.

Does anyone know why investor-state might be less of a problem here?  Are the substantive provisions different?  Is it considered more of a problem where U.S. investors are involved?  Or have we just not seen the controversy yet in the context of this agreement, and the protests will soon begin?