Rode lots of great high-speed rides, including Space Mountain, Everest, Tower of Terror, and Rock 'n' Roll Roller Coaster. My 8-year-old, Ben, was so excited about Everest and RnR Roller Coaster, that I decided to look their stats up online and also found many YouTube online videos. (Everest, RnR, ToT)
So, it turns out the RnR Coaster is "one of the most powerful coasters in North America" accelerating 0-57 in 2.7 seconds, generating G-forces of 4.5 to 5 depending on where you are seated (stats from here).
A long time ago, I was inteviewed on the dangers of roller coasters (with respect to head trauma, which there appears to be none), but I was naturally interested in the possible dangers of such a fast acceleration. Fortunately, UPenn researchers had answered this question back in 2002:
They acquired G force data from three of the most popular and powerful roller coasters in the country: the "Rock 'n' Roller Coaster" at the Disney-MGM Studios in Orlando, Florida; "Speed -- The Ride" at the Nascar Café, in Las Vegas, Nevada; and "Face-Off" at Kings Island, Ohio. Using this data, they calculated peak head accelerations in three directions, assuming the head did not strike a surface. Even considering the worst-case scenario, the researchers found that the largest forces experienced on roller coasters were far below those that are known to cause injury.
I wish I could prove it was my line, but when I was interviewed by the Boston Globe I said "it is more dangerous to drive to the amusement park than to ride the roller coaster" but they didn't include that in the article. However, someone quoting the UPenn study, concluded:
It does not appear that roller coasters produce high enough forces to mechanically deform and injure the brain...
For healthy people who meet the size requirements for the ride, you are probably safer on the average roller coaster than driving to the amusement park,