JMac: I haven't tried to modify a CO detector. If you are successful at the CO mod, I would be interested in the results you have. Thanks for all the suggestions, they are all good points to consider for what each individual wants from their alarm system. As far as grabbing a hose or a gun, I have each DS7000 turn on different lights so as to know if its a fire alarm or a break in alarm. When away from home, each DS7000 has its own separate message recorded, one has message fire alarm activated, the other message is break in alarm activated. When at home I'm also able to tell the difference between the two DS7000 systems as they are located in difference locations and there is a slight difference in how each DS7000 sounds. In addition, I have a X10 siren (often referred to as the noisy cricket) activated by the break in DS7000, but not on the fire alarm DS7000.
I prefer to use two DS7000, one for security/break in and a separate one for fire/smoke alarm. I had previously mention that I also have a fire/smoke detector in the garage that could not be heard from inside the house. While at home this DS7000 fire/smoke mod now allows me to know if that detector is activated. If DS7000 is not armed, it will chime. If DS7000 is armed, if will alarm and turn on light for that detector on the DS7000 console. When I'm away from home and should this DS7000 fire/smoke alarm be activated, it will call the pre-programed phone numbers. If I select to listen in on noise inside home, I can not hear if the garage fire/smoke detector has activated. So far this has not happen. If I ever do get a fire alarm when I'm away from home and I can't hear any noise while listening in on the DS7000, then I will call my neighbors until I reach one that can do a visual check on my home. In the unlikely event I could nor reach a neighbor , then I would request the local police to check on it. They (police) are really good on doing things like that here in north Florida.