I am one who hates heights, but I had no issue with it. It does not matter which row you sit in, the view is basically the same. If you have a fear of heights, Omni-type may not be the best attractions for you, but I was able to do it. I did close my eyes at the very beginning just for a moment, but it was okay and I immediately reopened them. The sensations are real, so even though you know you are sitting in a bench only 30 feet off the ground, the attraction itself makes you feel otherwise.
But, I think you should try it anyway and if you do not like it, close your eyes and enjoy the smells and the movements. I think that if I can do it, anybody can.