I had an open shot years ago, was not a fan. Best I can remember, climbing was awkward and it wasn't comfortable for all day sits (which I do a lot of in early November). Sold it, bought a specialist sd and love it. I pack in a mile regularly, sit all day, climbing is easy. It's not comparable to the viper for comfort, but what you gain from having the open front is worth it to me. I have also shot a few deer while being seated in the sd, but you don't have full range to spin because of the sling seat. I have no idea if they still make the specialist sd. I've probably had mine for 10 years plus.