Answer for Z wave vs alarm

I like the DIY (do it yourself) method building the security system myself with Z-Wave because it gives me total control over its behavior, and allows me to easily integrate with other things like lighting, input from Tasker (for Android phones) for geolocation, SMS text message alerts, etc.
 
Any standalone home security system, even if you can integrate it with Z-Wave will still have most of its functionality hard-coded leaving you unable to integrate other things with it.
 
Hope that helps!