Love the concept. My daughter loves bats so I bought the HyperBat for her. A two stage rocket for greater heights. Goes together pretty easy, just take your time getting the motors in the booster to login up with the second stage. If I were to change anything it would be the grain direction on the booster fins. The go down at a 45 degree angle from the tube and are very easy to break off. O actually put a tapered brace 1/32 X 2 inches across both sides of fins to reinforce them. With its interesting profile it lives up to its name.