Big Thunder Mountain Railroad was the "big rollercoaster" for my 40" tall 4 year old. I think it was his favorite MK attraction and was second to The Tower of Terror overall. While on the ride, I shot mainly by using a wide angle, a high shutter speed, and just holding the camera out and guessing on my composition.
nice job under difficult conditions, esp near the back, that seems to me to have the most whipping feeling if i might offer something for consideration, try cropping out or cloning out those people up near the top of the one with the train of riders rounding the curve, i feel that would help draw the viewer into the curve more, you did a great job getting a sharp image here, at a great angle, makes me feel as if i'm really in the last car