RE: Safety Harness....
I got a Seat of the Pants vest for Christmas, VERY easy to put on, no playing "guess which hole your head and arms go through", put it on like a vest, attach leg straps and off you go. Has D rings on the hips to use as a climbing belt for hanging stands.
Pat on the bowsite a while back did a field test of several including the hunter safety system, just about castrated himself with it. Supposedly its been redesigned since then, but check first.
I also, this year, started using a climbing rope system to be attached all the way up and down to/from my hang on stands. got it from a guy on archery talk, $30/setup. High quality climbing rope, stays attached above the stand and by the ground, sliding prussic knot you attach to to climb. I figure it slows me down by about 5-10 seconds per trip up/down the tree. Myself and family are now never off the ground without being connected.