Large APS-C (23.2 x 15.4 mm) sensor Large sensors provide shallower depth of field and a nice blurry background for your portrait shots.
Very High Resolution Sensor: 20.0MP Sony QX1's 20.0MP sensor will provide larger room for cropping, and you will be able print your portrait shots larger with more fine detail.
No Image Stabilization Lack of Image stabilization may result in blurry photos especially in long exposures and at long focal lengths
No Built-in Viewfinder In the lack of a a viewfinder, holding the camera away from the body while using live view is not very stable, especial with heavy camera bodies and lenses. Besides, LCD screens are very hard to read under bright sunlight.