The original one is still ok (only one time glued) but the printed one is more aerodynamic and can fly higher.
Be warned that the tip of the rocket can cause some pain or even damage light things, the rocket is light but is quite fast!
In the blend file there is also a version with non slanted wings, flies maybe even higher but maybe not as that stable.
This is the launcher
It should also fit on the hand launcer they sell.
Much fun for father and son.
The modell has some (cosmetic) issues but prints fine.
One perimeter, NO infill (weight!), detect thin walls, two bottom layers filled, no top layers filled in Slic3r 1.2.9. The slicer complained about "some" errors but I did not care :-)
Printed in PLA. Better first print only a part so you can check if the inner tube fits good on the launcher!
The rippling on the top inner tube is there for a reason, makes the head more rigid and easier to fill the top.