I haven't been on a roller coaster since I was VERY young (pre-emet), and now I generally don't like to go on any rides because of my emet. Some rides I don't mind so much, like normal ferris wheels and other rides that don't go too fast or loop or drop or... anything too extreme.

Only once have I been on an 'unsafe' (to me) ride. I was in junior high and a friend convinced me to go on one of those rides that spins in circles. I didn't v* but I spent the whole ride afraid that I would and was unable to enjoy it. I'm not sure I'm the kind of person who would find that kind of ride enjoyable even if I didn't have emetophobia, though.