Haven't fiddled with this lens too much yet, but the little I have, I'm impressed, and already planning more photo-outings with it. Attached to my NEX-6, this provides a package that is just fun to use, especially with the camera set to A (aperture priority).
Versatile fixed focal length; great in low-light with no flash
Pricey; slightly longer barrel than 16-50mm kit lens retracted