My first colonoscopy was without anesthesia, and it was as described above. A little uncomfortable on the one bend, but I don't even think I would put it at 7/10 (perhaps a 4 or 5—but not a sharp pain, mind you).
Definitely enjoyed the following times with anesthesia because, of course 0/10 as far as I know. Also, anesthesia just trips my mind—how seemingly time travel (going forward in time) seems to be involved.
Sounds a bit like the transnasal esophagoscopy I opted for recently in lieu of an upper endoscopy. Thin tube through nose, then down into the esophagus. Uncomfortable while threading it through (chest pain, like swallowing a sharp tortilla chip), but ultimately not a big deal, and done in-office in about 15 minutes.