First impressions:
Lens case came today. First off, this is a quality piece of gear. I am using it with two fairly large diameter zooms and it works very well. There's just enough room in the bottom when fully expanded to fit both lenses with their hoods. If either of the lenses were larger diameter, the second one would need to be smaller.
I put the lens exchange case, little gear pouch, and water bottle holder on the belt. With a lens in the case and a full water bottle (24oz., insulated stainless steel) the setup weighs in at just under 6 lbs.
Had a couple of false starts in positioning the gear. With the water bottle on my right hip it wanted to pull my pants down, moving the water bottle to the front right (in front of the camera sling) resolved it. The lens pouch sets just forward of my left hip and is easy to access with my left hand. Holding the camera with my right hand and using the left to swap the lenses is fast and easy. The little gear pouch sets between the lens pouch and buckle.
With my regular camera strap still attached, the elastic camera sling is really nice to keep the camera snug against your body when walking so it doesn't bounce around. The strap has a quick-release buckle, it's really fast to release and bring the camera up with one hand. I could see using this belt on hikes for that feature alone, never mind the rest of the gear.
Nothing is in the way of anything, and everything is accessible. The camera can be in the sling or just on the shoulder strap, either way is fine. With the camera in the sling the belt doesn't try to fall down, at least not yet. However, most of the camera's weight is still on the strap, it's just a coincidence that I have my strap adjusted to exactly that length. Serendipity! Next test will be in actual use, not for another few weeks yet.
There are more belt loops and several Caribiner points around the rear, but I don't think I'd want to add anything more to the belt, and really not sure what I'd need to add anyway.