It takes 10-15 minutes for a regular colonoscopy, for such short time, does the side effect of anesthesia actually comparable to the "major surgery" that can easily last 5-10 hours you mentioned?
I always get the same stuff Michael Jackson was using. You fall deeply asleep for the duration, wake up pretty refreshed, only downside is that I am usually besides myself for the rest of the day. Good thing you aren't allowed to drive for the next 24 hours.