I was oversold when I acquired ADT services. The glass cracking devices cost me almost $1500. Their price to me was significantly higher than published ads and mailers. The glass cracking devices sound the alarm if you sneez and/or drop the soap in the shower. I may recommend them but not to my friends.
ADT's service person was knowledgeable and efficient. Large order, he had to come back to finish. Checked in with me, long distance, when finished. Service center is great about checking in when a question arises. I don't go for a lot of bells and whistles, easy to understand and operate.