The U-can-dos are good flying planes, but they are NOT designed to fly straight and level at full power. If you do, you can expereince all kinds of bad things, including having the tail break off in the air (happend to one at my field, and another guy found cracks). They aren't overbuilt like many planes, so they can be easily damaged. But if you reinforce the tail area, and fly it gently, it should be fine.