I prefer a mic on a stand to a small mic mounted on my guitar. By getting the mic out in front of the guitar you get a better blending of the sounds from the instrument's top, sound hole, and strings. An SM57 or SM81 works fine for me.
I did own a DPA 4099 and sold it. Audio Technica now has a new instrument mic with a guitar mount priced at $349 if you want to go that route.
ATM350GL
FWIW I've had good experience with Audio Technica products although I have not tried this mic.