Interesting, I haven’t used a sonoff rf bridge, but since your post I did some research. The bridge is based on a different (non TI) chip.
I now have a TI CC2652 which is a lot better than the CC2531, it is faster, has room for far more direct clients. I get better range than CC2531, but maybe a sonoff zb bridge may be even better in terms if range.
sigh I don’t know what will happen if another package turns up from China in the post 
hm… dont ge me wrong. The range of sonoff bridge is not “that” good (but the dongle is bad!). Currently I have a hue bridge and two xiaomi gateways, and both seem to have a better range, of course, they have their limitations about compability with other devices. I would be very interested if there is way to transform a sonoff bridge in a router instead of coordinator.
Another thing to bear in mind is that a dongle seems to work better when attached to a usb cable, it gets it away from all the interference of your computer.
Just a small update on the range issue. I was doing my tests using a sonoff movement sensor and it was failing after moving one “room” of distance and I blamed the dongle/bridge. Today i did the test using a xiaomi sensor and it worked. I put the two sensor together on a room and xiaomi just works while sonoff went mute. (Even so, bridge had a better range than the dongle.)
Does anybody know how fast this SNZB-03 report “no motion” event?
Is it like in Xiaomi/Aqara after 2 minutes or it is faster?
PS. Just found this video: https://www.youtube.com/watch?v=yyiEr-v7_T0&t=416s
And it seems to be around 30 seconds, but wondering if the time would be the same on Home Assistant platform using zigbee2mqtt or ZHA.
I assume yes, but maybe someone can actually measure this and share it with us.
Mine reset after exactly 1 minute if no further motion detected
But I am using ZHA not MQTT 
Best, JR
I tried the motion (SNZB-03) and temp (SNZB-02) sensors. I can get them to join the Zigbee Network with no issues but they all fail to report anything. This has been a very disappointing experiment as I expected Sonoff to deliver products that were much better built.
Hello all,
I have question about SNZB-02 and 03 : is it possible to use it with no flash with Zigbee2mqtt and mosquito (and no Sonoff Zigbee bridge) ?
Thanks for your feedback.
I use a SNZB-03 with Zigbee2mqtt. The 02 should work too, but since I don’t have them, I can’t confirm it.
ok ths. From others users, seems working.
Waiting now for my order to test it 
can someone explain how you paired these to home assistant, without the sonoff zigbee bridge?
Zigbee2mqtt via whatever dongle you prefer whether it be conbee or one of the Texas Instruments
Would it be possible to just use ZHA (the native HA Zigbee integration) instead of Zigbee2mqtt?
I use a HUSBZB USB stick in a RPi running HA. I’ve had no problem with other Zigbee devices. They just work right out of the box. Is there any reason I shouldn’t expect these to be the same?
I finally got it using the same usb stick as you…I had to remove and reseat the battery, and long press the sensor reset button until the LED blinks 3 times (red).
They should operate the same, but they can be fickle. Motion sensor decided not to trigger yesterday at all but seems fine today so I have no idea what was going on.
Exactly the same for me with a ConBee II ( 1 minute, it’s long).
I’m looking to reduce the time, but i don’t know how to do
@timmccor I have a Conbee 2 attached via ZHA to my HA installation. I just got these sensors and neither the PIR nor the contact sensor was recognized. Any ideas?
Similar situation here.
Conbee 2 with ZHA Integration (hassio 2021.01.7).
Sonoff MS01 (zigbee motion sensor) is recognized but the state is always on (permanent motion detection / yellow). Doesn’t respond to movement.
Sonoff WB01 (mini switch) works great.
Conbee 2 with deconz doesn’t recognize the motion sensor. It only works with the mini switch WB01.
The SNZB-04 i received had CR2032 battery. Which is a huge plus in my book as they’re more readily available and cheaper.