Nikon 40mm micro lens?

I currenlty own the nikon d3200 with 18-55mm lens. I'm considering the nikon 40mm micro lens, but is it a good choice?

It's a good choice for making very small objects seem large. It's not good for making far objects seem near. It's good for some portraits but not good for large group shots and landscapes.

It is reputed to be sharp, and it allows you to take very closeup photos. Less expensive than other macro lenses of similar quality.
Disadvantage is that the working distance is short. Not as good as 60mm for portraits. Not as good as 100mm or more for live insects.

Typically, one buys a short macro like this one or a 50mm macro for copy work. That is to say taking photos of prints, slides, or just about any inanimate object where being physically close to it isn't going to be a problem.
However, those who are shooting flower, bugs and insects, and various other things outdoors will avoid short macros because of the short working distances. Those photographers will prefer the 90-105 range of macro because they can be further back. Being further away from the subject means that they're less likely to spook an insect and that they're less likely to cast their own shadow onto the subject. Using a flash is also easier as the camera/lens won't get in the way.

Of course, you don't have to get a macro lens to get macro shots. You can spend a lot less on an extension tube and attach it between your current lens and the body. If you look at the back side of any macro lens, you'll see that they all have the rear element recessed deep inside the tube of the lens. Having the rear element further away from the sensor/film is what allows for close focusing distances. That's how an extension tube basically works. They're around $100 for one that transmits data between body and lens.
Here's a link to compare the image quality between the various lenses for and by Nikon DX cameras: http://www.photozone.de/...lens-tests

Suggest you set your 18-55mm kit lens on 40mm, put your D3200 in Close up mode and see what you get. You may discover that it does all you want, or you may discover that 40mm is not a good focal length for you. Then again it may just whet your appetite for the very sharp Nikkor 40mm f/2.8 micro lens.

Don't take the nikon 40mm. It seems attractive, but to achieve a 1:1 ratio, you'll need to be so close to the subject (maybe 3,4 cm away from the front element of the lens) that you'll scare it away. I suggest the tamron 90mm f2.8. It isn't too expensive and allows for good working distances as well as doubling as a short telephoto lens.