My first scope I was conscious but 'out of it' and it went fine, can't remember any discomfort - I think I was just gazing at the TV of my insides high as a kite quite happily lol.
Second scope 6 years later - during that time I've somehow manage to develop severe anxiety in hospitals and so they fully sedated me as I was a freaking out hyper-ventilating mess, I did come round slightly during it but they just knocked me out again I have a very vague memory of it so I think the nurses were right on top of monitoring me and didn't give me a chance to come round fully. Also I knew the doctor who was doing it and they were aware how freaked out I get, at least the doctor is aware that this is a concern of yours and will hopefully be on top of it.