I'm not sure that its roughrt or jerkier than before. The new ST has several different versions. You don't know in advance which combo of scenarios you're going to get. But I have found that I'm more prone to motion sickness with some of the new combos than I ever was with the old one.
I never had problems before, but now if I ride it more than once at a time it does give me motion sickness. DH loves the ride and wants to see as many combinations as possible. Which means when it is quiet one ride after another.
But the new film, with the 3D, does make it feel different. I can ride it once, barely. Sometimes I have to close my eyes towards the end of the ride. Oddly, it doesn't bother my dd, who has tossed her cookies in my car more times than I can count.The refurb was the film, not the actual simulators, so there really hasn't been any change in the physical experience.