OK, I hate to be the wet blanket but I didn't like Mission Space at all. I followed all the good reccomendations here when I rode last Christmas. I rode late at night in case I got sick from it, kept my eyes on the screen the ENTIRE time, NEVER closed my eyes, did it all. I felt OK after riding it (though a bit on the queasy side). By the time I got back to Port Orleans I was so queasy and sick that I skipped Christmas Eve dinner, something I planned for months.
Next morning I woke up feeling not quite so queasy but instead I felt dizzy. Well, the dizzy feeling remained for the rest of my trip and actually got worse. The best way to explain it is that when I closed my eyes I would lose my balance and fall to one side as if I were spinning.
When I got home it got so bad I couldn't even drive because I was always dizzy. Had to go to an ear, nose, and throat specialist who put me on steroids to overcome the problem. He said it was definately Mission Space that caused it because I must have some inner ear/motion sensitivity. The diagnosis was Labrynthitis which is basically a problem with the part of your ear that controls balance. The Doc said that part of the ear has fluid which helps you keep your balance and if you spin around violently (as in Mission Space) the fluid can be disturbed and you can lose your balance for days, weeks, or even months! For me it lasted about 3-4 weeks and it was awfull.
Now, obviously plenty of people ride it and are OK but if you have ANY sensitivity to montion I strongly suggest against it. I'll be honest with you, it isn't that good and believe me, I am a space nut so anything space themed, I am there! It's such a short ride to risk feeling ill.
I understand the curiosity. Before we went I researched it to death and even though I was scared, I felt well prepared to deal with the ride. I went against my better judgement and big mistake! Never again! If you ask me, IMHO, Space Mission doesn't belong in Disney, it is not a Disney ride, more like a Universal ride for thrill seekers.
Just my 2 cents! Good luck no matter what you do and do have fun on your trip!
Monica