If you go by the pistils alone, you're probably going to harvest too early. You really should check the trichomes. I made that mistake before, going solely by the pistils, harvested at 60 days flowering, and they weren't done. I'm at 65 days now, and still not (quite) done, although if I just went by the pistils they looked done several days ago. You've put this much effort into it; might as well finish it up the right way, and check those trichomes before you hack.

Also, I read that the Dutch had figured out that 72 hours of complete darkness at the end of harvest can, with some strains, produce as much as 30 percent more THC, so that's something to consider. Worst case, doesn't help, doesn't hurt. Best case, more THC (if your strains react favorably to the extended darkness). One thing that the article I read didn't say is whether the trichomes continue to mature during that 72 hours of darkness. I really wish I knew whether they do or not. Guess I'll find out, as I'm going to do a final trich-check tomorrow then start the 72 hours of darkness, and check the trichs again after the darkness.