I tried the VT one hike. With 20 lbs in it and along rugged trails, the 2 lb VT was almost as comfortable as my 7.5 lb Lowe Alpine. I had zero weight on the shoulder straps, but compressed the load with the side straps vigourously. When I put weight on the shoulder straps (just to test my tolerance for "no hipbelt"), I wished they were wider. The hipbelt was super comfortable and load bearing.
I carried a Ridgerest pad rolled into a solid tube and on the outside of the pack, under the straps along the front. (maybe that's why the pack didn't sag).
I could barely reach the top of the side pockets to pull things out when the pack was on. Putting things back was possible, but irritatingly difficult. I used a 3L bladder filled to 2L, but it didn't fit in the slot between the foam and pack bag without causing an uncomfortable lump.
The load lifters didn't seem to do anything except close up the gap between the foam backpanel and packbag. This may have been because the torso was about 1" too long for me and the load lifters were approximately even with the top of the shoulder straps.
I thought the extension collar was way, way, way too long, and a cinch-cord top covered by a flap with a zippered patch pocket would be much better. I also thought it needed a big mesh pocket on the rear for my wet tarp, ground sheet, and rain gear.
I didn't find putting the pack under my legs when sleeping to be as comfortable as a pad, or convenient (then I had no place to put my other stuff to keep the creepy crawlys out of it).
I found the materials to be plenty durable and hold up to vigorous stuffing of gear, going through off-trail tree-type brush, and non-carefully setting the pack down or pulling it toward me to get something out while taking a break on rocky overlooks.
Overall, it was a great pack. Not perfect, but close.