We have had RSS for a couple of years. The cost is $25/month, added to our monthly electric bill. The installation was handled professionally and to our specifications. As it was a retrofit, battery power is used. Unfortunately, a backup cell phone is not available in this area. The company is quick to answer queries and service problems.
The monitoring office has contacted the police twice, in a timely manner, since we activated the service. Fortunately, a break-in was not the cause. Police response time varies owing to manpower issues. It is not as quick as it is in a large metropolitan area.