To me, SN is not worth it IF you can obtain N.
Barbiturates like N are neuroprotective. It's all about in the worst case scenario (if you are firm on CTB) being rescued. While you may have rhabdomyolysis (muscle breakdown --> painful muscle) from pressure injuries, deconditioning (muscle loss --> weakness) from being intubated on a ventilator, potentially decubitus (back) ulcers or post ICU syndrome, your mind is way better protected.
Depending on how far you are out, SN can lead to hypoxic brain injury. For anyone who already has difficulties concentrating or issues w/ short term memory, they will be significantly magnified after being rescued from SN CTB.
N CTB has a quicker onset of action, vs methemoglobinemia CTB from SN takes time to develop. It is essentially a slow strangulation process (your body is getting deprived of oxygen) without the feeling of constriction on your neck or the feeling of your head exploding from compression of your jugular veins.
Finally, there is no antidote for barbiturate reversal (like there is for benzos, and flumazenil is really not that great). Methemoglobinemia has a very effective reversal agent (methylene blue), and clinically, its not difficult to recognize (the blueing of the skin, if someones oxygen levels isnt coming up with supplemental oxygen and normal lung imaging), so its more likely to be caught more quickly.
The downside here barbiturate overdose recovery is much more likely to have an expensive ICU stay (b/c the way you treat it is ICU level supportive care), and if you have dependents OR are on other people's insurance, you are likely to leave them with an expensive bill.