ADT here. It was a bit pricey, if I recall from two years ago, roughly just over $1000. Probably could have gotten it cheaper but its a piece of mind, especially for the wife when I'm not home. As for when I'm home, like someone else posted, its a heads up to get up and prepare to address any threat. There's a lot of competition around here but ADT seems to be one of the ones that hasn't changed names a million times or gone out of business. I've seen some of their 'response units' and was far from impressed a few times. On the other hand, I've seen two retired le who were in excellent condition, so who knows what you'll get. I'd say its worth it though, if nothing else, atleast if something happens, whenever someone does respond, they'll notify the police.
The views, comments, and opinions posted above represent soley the views, comments, and opinions of myself alone, and to my knowledge do not represent the views, comments, and opinions of anyone else or my department.