I have two novas.
The reason I have two:
I bougth a nova synthetic for home protection w/ 18/5" barrel. As I used it more at the range, I started to use it more and more for breaking clays. I never had a jam or misfeed problem that was not of my fault in short shuking.
When I finally realized that a cylinder bore short barrel is not the way to go, I decided to get a new barrel, but a new barrel cost more than a used gun with the 28" barrel I wanted. I went with the used gun.
The first time I shot the used gun the shells would not eject from the magazine tube. The previous owner had let water sit inside the magazine tube and it rusted the spring and inside walls of the tube. The rust left a rough spot that the magazine follower was catching on. After I filed it down a bit and ran some steel wool through the tube, it has functioned perfectly.
I now have over 1,500 shells through the gun without even so much as re-oiling, running a boresnake through the barrel, or anything that closely resembles cleaning the gun without a single feed problem.
I hope that this helps you in two ways:
One, keep the tube dry.
Two, the Nova is awesome in its utter reliability if nothing else.
Timothy