Certain Vs Uncertain Death

Is waiting for 'certain' death easier to handle as opposed to death that is uncertain?
Most of us feel that killing a person in one blow is less of a punishment than torturing a person physically to death. Dostoevsky thinks otherwise.

Is the mental torture that entails awaiting 'certain' death, say on an electric chair, far more difficult to endure than enduring physical wounds from multiple gunshots? There is some uncertainty in the latter, in not knowing at exactly what point one dies.

I can't comprehend how either of the two would really feel. But extrapolating from my present frame of mind, I feel that 'certain' death would be easier to handle. I don't feel mentally uncomfortable with the idea of my own death, right now*. I feel and know it is inevitable and I even do not value life, my own life, to a great extent. Given that, I'd prefer the mental torture, if anything, to the physical torture.

* This is a very general statement and has its origins in my existential outlook to life. This shall be explained in another post. Meanwhile I'd appreciate if no judgments are made about my state of mind or life!!