Endoscopy up the way is not bad at all...the worst bit by a long chalk is downing the disgusting laxative drink you have to take the day before...it doesn't taste bad, there's just so much of it.
Endoscopy down the way is another kettle of fish. I opted for no sedation and I never ever would do that again. I couldn't say it was painful, but very uncomfortable. They blow air down, so you're continually burping huge burps. And gagging quite a lot. If I ever have to have it again,(hopefully not) I'm definitely going for the sedation.