I'm just finishing the construction phase on a Nightwing today. It's been a fun build with lots of balsa work (which I enjoy) and a bunch of paper glueing and shaping, which was a bit more challenging. If I ever build a second one I'll do it better, now that I know how it all fits. I had the same thought as Nick about the tight space for an 18in chute, but too late to alter the shock-cord mount. I did add a good length or Kevlar line to extend the shock cord. The nose is large and heavy (and weighted with clay), and could really stress a short cord, or whip-back and damage that nice balsa.
Filling and finishing this rocket will be some work. I bought the rocket at my son's insistance, and he wants it painted "just like on the package" (we'll see...).
If you like a longer, more challenging build than the average Estes kit, this is a good option (especially at a bargain price.) I'm glad to hear that it flies well too!