Coming from 20+ years of PIM part design... I haven't had much luck with living hinges in SLS applications, at least not any subjected to cyclic deformation. That's not to say that there aren't some materials out there that could prove successful or print consistently to optimum thickness. If so, I'd be interested in hearing about those.
All that aside, I have had great luck and recommend the use of an integrated hinge instead. Spherical male with conical female receiver is quite easy to integrate into most designs with a little forethought.
Best regards
