Riding in one of these planes is unlike anything you have ever experienced. I've done skydiving, plenty of roller coasters, and all sorts of other things, but this hands down wins as the most exciting, adrenaline pumping things I've ever done.
The cost is high, so be sure this is something you can handle. If you're going to be throwing up and miserable three minutes in, you might be better off getting a cheaper helicopter tour of the area or going on one of their more tame flights. I went with Afterburner Aerobatics flight. The pilot was basically willing to do anything, and it was a blast!
I arrived at the hangar. They then explained what we would be doing and some of the mechanics behind it. After a small training I was ready to go. We rolled out of the hangar and took off to the sky. The pilot was friendly and good communicating back and forth with me on what we were about to do as well as checking to see how I felt. We did the basics, barrel rolls, stalls, loops, and then we got to the crazier stuff. I don't even know the names of the maneuvers we were doing, but we were flipping and twisting through the sky like crazy. I'm sure the pilot says this a lot, but according to him I went through more maneuvers than any other passenger he had flown.
After the flight I felt fine. On the way back to Las Vegas we stopped, I threw up, and that was that.