I have lost count of how many times I have had colonoscopies and gasrooscopies over the last 20 years and it's not because I am tougher than anyone else. It is because I want to see what is going on inside me.
The discomfort is minimal and I have never experienced anything approaching what you would call pain.
As far as a Colonoscopy is concerned, the fasting and Moviprep cleaning is worse than the actual event.
Last time I was in was December, and the nurse asked me why I had not opted for sedation. I answered, when I leave here I am going to do some Christmas Shopping and then walk home to get rid of the gas!