I purchased the GG Gorilla based heavily off this review and other research but am planning to return it,
Overall it seems great, but the shoulder straps are incredibly flawed and uncomfortable. They literally cut into your neck. They are far too wide, lack a J shape that pulls them out to the sides around the neck, and the Velcro is on the inside (inexplicably) and extremely abrasive. Maybe they work well for individuals with extremely thin necks, but for people such as myself with broad shoulders and necks I recommend you look elsewhere.
Other minor criticism is the stays should connect to the hip pack. Puzzling design decision since the stays reach right next to the hip pack and a simple pocket is all that is needed to pass some load to the hip strap.
Very unfortunate because otherwise it is a great pack. Very impressed by the quality of construction, but an uncomfortable pack is just useless.