@DyslexicForeigner ,
Whether it's easy to get sodium azide doesn't matter, only if you can get it. It shouldn't be a problem in the USA, tricky in Europe.
We don't know how 'peaceful' SN really is. Basically, death occurs by depriving your tissues of oxygen. Nitschke has been advocating SN, I don't trust him. Something may appear to be peaceful, but how do you know what a person is experiencing ? Experiences probably vary.
It's (almost) fully reversible with methylene blue. We don't know how long it takes to lose consciousness, this likely varies. If it takes many hours and causes great suffering, will you be able to resist calling for help knowing that the process is reversible ?
Sodium azide, in the right dose and assuming you took the right dose (high enough, 10-20 gr should definitely be enough) of the right antiemetic at the the right time, on an empty stomach and empty small intestines the probability that it kills you is (near) 100 %. I think Nitschke described two basic reactions, one involving a quick loss of consciousness, the other 'ominous'. Especially if the former does not occur, expect it to be extremely brutal. Likely, (much) worse than cyanide.