Do I need a ELK-P212S supervised power supply?


I am planning:
Alarm    ELK-M1GCB
M1 Ethernet Interface    Elk-M1XEP
16.5V AC transformer    ELK-TRG1640
Data Bus Hub Retrofit    ELK-M1DBHR
M1 16 Zone Input Expander    ELK-M1XIN
Wireless Receiver for GE Crystal Transmitters    ELK-M1XRFEG
All in the same box. Do I need the elk Supervised Power Supply ELK-P212S?
I am a little unclear if the M1 supervises the battery and power too.
I believe you will be fine, but I would seriously consider an Elk Kit as it might be cheaper (and include a keypad and speaker).
The Elk-P212S would be more of use if you were going to locate an expander card away from the Elk main board and power it separately AND wanted supervision of that power as well.