I personally think that Mission Space has more "barf" potential than Star Tours or Body Wars, but as you can tell from reading the experiences thus far, everyone is different. For myself, I can be moderately prone to motion sickness, although Star Tours and Body Wars never bothered me. I approached Mission Space with some trepidation, but I was very careful to do exactly as the instructions said - keep your head back, always look straight ahead and never off to the side, and don't ever close your eyes. There is cool air blowing gently on your face the whole time, which helps, and I made an effort to breathe regularly and stay relaxed. You're asked to push a button on your control panel at some point in the landing process, and the button you're supposed to push flashes at the appropriate time. To avoid taking my eyes off the screen, I mentally located which button was going to be mine - it depends on which seat you're in - and when the time came, I noted the flashing in my peripheral vision and pushed the button without having to look at it. Of course, nothing happens if you don't actually push the button - it's just to make you feel like you're more a part of the experience. But if you're not prepared, you could be tempted to look away from the screen to find the button, and that may not be good. The most intense sensation for me was the abrupt feeling of "weightlessness" after the liftoff. It wasn't nauseating for me, just very weird, and it helps to be prepared for it. Overall, I felt fine after the ride - just a tiny bit lightheaded. It was an amazing experience, and I was glad I did it. I hope you take the chance on it.