I've also been scoped every which way. Gastroscopy (tube down the throat) is, to me, sheer torture. Colonoscopy prob'ly would've hurt too, but they offer a decent anesthetic as a matter of routine here, whereas for gastroscopy they need your cooperation so you only get the anesthetics you seem to need as the procedure proceeds. Anyways ... what with the sedative they put me on, colonoscopy was pretty much painless and kind of fascinating, unless I was in serious pain before they started. The first time or two they even let me look in a "student scope" that kinda branches off the main scope so that two eyes can see the same view. The doctor attached the student scope when he was done taking his biopsies, then he explained where and what we were seeing as he slowly withdrew the scope. Fascinating! Not often you get to look deep into your own insides.

Oh, about time expectations: Because of the anesthetic, I had to doze on a recovery gurney for a couple of hours after before they would let me leave. Accompanying partners were allowed in then and the doctor came by towards the end to review the information when the patient is fully alert. At least, that's how it's handled here at my local hospital.