The sound of the mic is very natural and definitely improved the tone of my primary acoustic after I changed the stock mics to the Shadow NFX-AC.
However. The mic is very responsive when it comes to touch. Touching the volume know will very likely make a sound through the mic. (About the same sound as when you take a singing mic out of it's clip)
Applying the mic could be a bit tricky, you may have to adjust the bridge of your guitar to make it fit.
But if you're handy with guitars and don't mind that the mic may produce some sound when touching it, the Shadow NFX-AC will definitely get the job done.