I have motion sensitive lights all over outside, and 4 security cameras that I can access from anywhere.
My NN is home 90% of the time, as they never go away or out much, so thats a good security system for me.(I was told by the previous owner at my closing 25 years ago, youll never be robbed, the NN is always watching, works out for me now)
Im pretty sure if a criminal wants to break in, nothing will stop them, but the cameras and lights and alarms will be a deterent for some local moron who is looking to make a quick grab what he can and run.