Ooh, yeah. i'm with you (not literally).
I've had a few the last few years, the laxative (Moviprep I get given) is the worst part by far. The procedure is a walk in the park in comparison.
Yeah I get Movicol or Moviprep, its easily the worst part of it all, going to the loo every 10 mins for 4 or 5 hours, I had about 6 down the years, just drink as much liquid as you can possibly drink keep it lubricated or its like firing a scattergun.