Initial fit testing, I can get the Ribz up high enough not to interfere with my belt, so that works. There is a lot of storage room in these; I didnt get a big chance to play with it too much yet, but I did put my survival kit in it & drove around for an hour with it. My initial observations is that this can hold quite a bit of gear. However, as it is against the ribs, I would suggest soft kit only-I have some of my gear in a small mess tin, and it was uncomfortable while driving. Easy enough fix.
Another minor annoyance was the upper cross strap (sort of like part of ah H style harness). This crept up a couple of times, and irritated my neck. I found two solutions; first, ensure it is low enough to avoid creep. Two, wear collared shirts-it gives something for it to catch on before your neck.
I will be on vaca starting next weekend, so I dont think I will have a chance to give it a run with a pack for the next couple weeks. I did put my 3 day pack on with it, and, I cannot buckle my sternum strap, but that was the only interference. And, this I just have to fiddle with. The one thing I dont like at all is that the material makes crinkly noises-its durable, for sure, and could prove to be warm, but it is louder than my other gear-not an issue once its on, but taking it on & off, it is quite loud. This is purely superficial though-I dont like loud noises in the woods, including any I make .