Really interesting thread so far. It seems you guys are the experts on skydiving/550D. With Sony CX models there's an issue if the model has optical image stabilization, which will bounce all over the place in freefall. I'm thinking about buying a 600D, which is pretty much the same as the 550D. The standard bundle comes with a 18-55mm IS lens. Have you experienced problems with this image stabilization in freefall, and if so, did switching it off solve the problem?