I picked up the smallest option because size & weight are a primary concern for me, but I'm now thinking of adding the 9 inch version to my kit because of how much I like this "magic arm." I had seen these raved about on Youtube in almost every photographer's "what's in my bag" video. I never thought I would need or want one, but all it took was one occasion when I couldn't find a place for my action camera for me to justify picking one up. I now can see why everyone raves about these tiny arm mounts. They are extremely useful for all sorts of gear, from lights to mics to small cameras. I use the small arm option to mount my action camera to objects in the environment or to attached the action cam to the bottom of my full sized camera for some POV footage. This arm is well built and sturdy enough to hold gear that is much larger than expected. However, because of the sturdy build quality, this is not light. Even though it's small, I don't know if I would add this much weight to a backpack for a long distance hike unless I knew I'd use it a lot. The turning handles are large and easy to tighten and loosen, which is much appreciated due to my lack of hand strength. The 1/4" tripod screw base and the alligator mouth clamp have rubber surfaces to make certain the grip is firm without damaging what it is attached to. On a pointless, superficial level, I like the small color accents used. I know the orange and black is a K&F Concept brand scheme, but it happens to look really nice with my Sony camera system, which uses the similar color orange in its design language. Overall, I'm very pleased I finally picked up this magic arm.