We chose Alarmforce because of it's voice challenge system. Figuring that 99% of alarms are false, we wanted an easy way to cancel an alarm as well as avoiding inadvertantly triggering it. Alarmforce doesn't send the police if you respond to their dispatcher with a valid password. The system can be armed/disarmed by any phone in the house. Much handier than a keypad. We are completely satisfied with their quick response, ease-of-use and customer service.
The installer arrived on time on both occasions (we needed an upgrade after expanding our house). He knew the system thoroughly and customized it to exactly what we wanted.