I just bought a Summit Viper 2 weeks ago. When guys here were saying how well they bit into the tree that was the understatement of the century [8D]. You're not going anywhere in that thing. Comfy as heck too. My only beef so far with it is I wish the platform was a foot longer. Not a big deal just an observation. It packs 10 times easier than I imagined too (once I got the hang of it). The only not so quiet part IMO is taking the cables out to wrap around the tree. Climbing the tree itself is quiet as can be. All in all I'm very happy with it.