the only bad thing is that it takes 1/3 your health just for one click(it stays on for a minimum amount of time) you can hold it asd long as you want till your health runs out. to start ppl out i usualy go up to the biggest hill i can find je tup as high as i can then ski down it and your probably going over the minimum speed to activate over drive. any questions feel free to message me or write on my wall ok??