Not sure about the Viper.
But I've got a Cobra X-4 and the seat is too noisy in stock form where it rubs against the back bars. Try it an you'll see. Strap it to a tree and set it up as you would when hunting then sit in the seat and shift your weight back and forth, side to side. Makes a rubbing noise my deer won't tolerate (learned the hard way

).
To "fix" it I wrapped the metal back brace portion of the stand (where the seat contacted the bracing) with cloth camo tape. The tape in between the two materials made the noise almost non existant.
Have fun hunting with it!