Both systems offer exceptional protection and support, so the choice really comes down to your unique needs. For someone who wants their home to be fully automated and for their devices to talk to one another, Nest is the easy choice. While more expensive, the system offers excellent connectivity and added products like the Nest Tags and connected lock.
3 - If you do not answer the alert fast enough, you are locked out-- even though someone is standing at your front door. You cannot "turn on" the camera from your phone or tablet. If someone is there and you do not have an "ACCEPT" button on the screen, there is just no way to see or talk to them. This is obviously a software flaw. You should always be able to "wake" a camera remotely and talk to a person at your front door. Or maybe you just want to see the view outside your front door. You should be able to access the camera / microphone and enjoy your front yard.