You can use the doorbell to answer your visitor's calls at the door, while having a 720p Video of the person that is at the door, andusing 2 way audio. The video quality is excellent, and it does not distort too much due to the use of the fish eye lens, toprovide the wide angle. It is much better than the video on the Ring bell of a friend. Even though the RING bell is 1080p,and wider lens, but the distortion is much more noticeable. Installation was very easy, with the exception that my transformer only provides 10V, and it initially did not work. Itconnected and installed fine, the button light went to a steady blue, but as soon as I pressed the button, the led colorwould change to Green and the chime would "try" to sound but would cutoff immediately. I thought I needed to install theadapter that came with the unit, but when I checked the voltage on my transformer, it was 10VAC, and as I pressed thebutton, it would come down to about 9. 75V. So, I went to my local store and got a 36V Center tap transformer to replace the10 V one, using the center tap to provide 18VAC. When I got back from the store, just in case, I pressed the button on theGREET, and it worked fine with the original 10VAC transformer. I waited a few minutes, and tried again.