There were 10 of us last month, one of whom (not a big thrill rider) didn't enjoy the experience. I wasn't with her at the time, so don't know if she followed all the best advice, which is:
Head Back.
Look Forward.
Not on a full stomach.
Not on an empty stomach either (Low blood suger is suspected by some as a prime culprit. We had hard candies to suck upon before boarding, but not during, the ride).
A few years ago at the fair, we had a tilt-a-whirl operator let the ride run for 4-5 minutes. Before that, any type of motion sickness was rare to non-existant for me. Since then, I usually don't want more than one spinning ride per day. Amazingly, the worst is a slow spinner at Paramount's Great America. I knew that MS would spin, but would have never guessed it had I not already known. No problems even though it was our first ride at park opening after a night of Blue Chuckles and Jungle Juice in PI. And I am practically a non-drinker; that was the only alcohol I've had since Oct. 2005.
In my opinion, the "horror" of Mission Space is grossly exagerrated. I would never have hesitated to let my son ride when he was 4.
Cheers.