The flagship Survivor is Griffin’s heaviest-duty case, and has been for a few years now. There are no significant changes compared to the iPhone 5/5s version, other than the subtle tweaks to the shape; therefore this review is heavily based on our earlier thoughts. The unit snaps apart into three primary pieces—a plastic tray, a rubber frame, and a plastic-bordered screen protector, plus the separate detachable belt clip. That last component…