Overall I'd say it's a quality kit if you've done your research and know what you're getting. The problem is more that reefers are never happy and always want to upgrade and buy toys, etc. for their tanks. Beyond adding a circulation powerhead, you really can run a NC stock and grow a reef. I point you toward Kidninja's tank if you want a good example of a basically stock tank- there are others I'm sure, but his comes to mind.
The higher end of NC's with the HQI and LED probably really can grow anything.
The Bad:
Hard to add equipment, particularly in the < 28gal sizes.
Tanks tend to run hot, will need to work out fans or chiller depending on your ambient temps (see #1- this likely means a mod if your house gets over 75-77 degrees).
Curved front can make it hard to photo.
Stands are functional and I'll leave it at that.
The good:
Compact.
Clean lines.
Quite a few mods have already been figured out for you.
Solid and sturdy now.
All the basics are there to successfully start a reef as long as you match your corals well to the lights that came with it.
Personally, I've owned 2 now and I like them. So does my wife because she didn't like how AGA's get to looking with equipment hanging all over them. If you have the space, an aquarium with a well thought out sump is going to be a better overall system, but NC's really are pretty good tanks.