The good

  • Build quality and materials.
  • The smallest 30mm equivalent lens for Nikon DX bodies.
  • Center sharpness at par with Nikon's 18-70mm AF-S G
  • Reasonably priced.

The bad

  • No AF ...
  • Slightly soft corner sharpness
  • The included front cap is too flimsy for real use
Voigtlander produced a solid lens, with unique focal length / size combination that no other company seem to currently offer.
Optical performance is good, but not brilliant. If you are keen on the viewing angle/size combination this lens has to offer, and willing to live with a manual focus lens, go ahead and buy this, don't forget that lens cap while you're at it.
If physical size isn't that critical, there are probably better options out there, the Nikon AF-S G 18-70mm is one example, which will give you similar optical performance at a larger package, but at a lower price, and with the benefits of a zoom that goes to 70mm, and a best in class auto focus mechanism.