In general you would use the 405-03 for most installations.
Yes, but...
The key decision you have to make is "how are you going to trigger the reversing relay?"
With the M1G you have several options...
1. You can use Output 2 in Voltage mode. With this choice, you would use the 405-03. But, this also means that your smoke detector sounders are also your burglar alarm -- the smokes will sound off for all M1 alarms. Also, to attach other things to Output 2, like an outdoor siren, you cannot use speakers, you have to use self-contained siren unit(s). Current on this output is limited to one amp, so tally up everything you are planning to attach, knowing that it will be driving all of your smoke detector sounders.
2. You can use a relay output, such as Output 3, or one relay on a M1RB, as your trigger. Here you have to write a rule so that a fire alarm activates the output you choose. Since you already have a power supply for your smoke detectors, for simplicity this would lead you to the 405-05, wiring its trigger contacts to the M1 Aux power (for example) through the relay. With this arrangement the power load on the M1 is minimal (only driving the relay during an alarm), and again be aware of the total draw of the smokes during an alarm and of the capacity of your power supply, which is supplying all of the alarm power.
3. You can use one of the 12 volt low-power outputs, such as Output 7. This would be the just the same as #2 above, but simpler because the output itself would have enough drive (most likely) for the 405-05 relay.
