I should point out that nearly all alarm systems can send you an SMS to your mobile regarding recent events (intrusion, fire, tamper etc).
Either as part of their range or a bit of add-on kit.
This kit starts at around £70
All a monitoring system does is send the same message via SMS or dialup/IP/3G or Redcare$$$ to a flunky who will check the system and decide to ring the Police or not.
Essentially you are paying extra to give the police a tipoff, when really insurance covers everything anyway.
Good luck keeping tabs on the SMS centres when they change their numbers. Be better off giving the money to your neighbour. If you go that way just buy a bloomin speech dialler and be done with it.