Which end are we scoping? Colonoscopy is often done without anaesthesia but tends to take longer than 2 minutes, so I'm not sure if that's what OC is referring to. It's uncomfortable, but that's ok. Scoping nose/mouth->stomach also doesn't come with any drugs, just some lube.
I've done it (it's standard in many countries). Honestly, it's a bit horrifying because you are completely at the mercy of someone else but it's bearable. Colonoscopy is definitely easier.
My only experience with global anesthesia was as a child waking up with a massive asthma attack unable to breathe so I try to avoid it.