SNZB-03 is zigbee, while the PIR3-RF is 433mhz-rf.
I ordered the one that was most compatible with the rest of my setup.
SNZB-03 ZigBee Motion Sensor, Wireless Motion Detector Get Alerts or Trigger Lights to Turn on.
PIR3-RF is a Wireless motion sensor used for your smart home automation security alarm system.
I only know: Brand: Sonoff. With the universal joint, the sensor can be flexible to rotate a full 360°horizontal angle and 90°vertical angle!