Hitting a stump is no fun on blasters. As is "casing" a dip in the trail. I've jammed my ribs on the throttle more times than I can count from going into a dip too fast and either having the front end dive or go straight into the other side of the dip. It hurts when you take a shot to the ribs.
Also riding gear is awesome. There is a big difference between your favorite pair of jeans and riding pants. Gotta love it