Poor Response Time on Panic Activation

We've been with ADT for over eight years now. I've been disappointed with their service in the past year due to poor response time and a somewhat unprofessionalism with customer service personnel. I have decided to cancel the contract and source another security company. Furthermore, the alarm system will now have to be removed and this is contrary to what I recall being said on time of signing up! I was told just the aerial belonged to them after two years.