I just managed it on the third try - it wasn't gagging that I struggled with but pain. I had been told the technician would be gentle and go at my pace, but he didn't. After I managed it I realised on the 2 times I had failed I had actually been very close - another few swallows - from it being in position. Would have been helpful if they had told me how close I was!
I was so uncomfortable that I thought keeping it in would be an issue, but I found I began to cope after a couple of hours. I was very aware of it for the whole 24 hours though and didn't sleep much. I was also very symptomatic but the results were entirely normal
Not something I ever want to repeat!
MMM