If you look under methods, it's essentially the night night method. Short answer is if you prepare and understand how it works for you it's extremely fast and painless.
https://sanctioned-suicide.net/threads/the-night-night-method.6834/
The "secret" to this method is that it only cuts off the blood to the brain, not the blood leaving or the windpipe so I'd consider it far more comfortable of a way to CTB.