I’m glad that you can still use Iris v1 devices now that Hubitat supports them. Grabbed a good lot of them from eBay for $2/piece! Can’t thank the HE team enough for adding support for these now that Iris is shutting down and people are looking about what to switch to from Iris.
Personally I prefer not to carry an extra item on my own keychain, but it also depends how reliable mobile presence is in your specific situation (it can be pretty variable).
But I also use a ST presence sensor for the keys that we give to my parents or in-laws when they are visiting.
It all depends on how you intend to incorporate presence sensing with your home and it’s automations.
I’m putting it in the glove box of two cars—and using the car’s power to keep it alive. We only have a 1-stall garage (home built in 1919), and when it detects that a fob is on, then a car is on in the garage and the door shouldn’t auto-shut. As with all good automation, this isn’t the only verification in my garage system
The other one will be for guests to automate different events and detect presence, since the fob has two buttons.
I was expecting reliability on all the Iris v1 devices to be a little flakey, but they’re great. Between the contact sensors and this, I’ve been really impressed.
I have 1 Gen1 motion sensor and hooked it up to Hubitat this weekend. When using it to turn on my hallway lights, it usually picks up motion and has the lights on in about 0.5s. Sometimes it was instant, other times it was about 1s but most of the time is was about 0.5s. I use it now for lack of motion to turn off the lights with a delay and it works great for that. I have it mounted on top of the door frame and it does not pick up my cat's motion, which is nice. Haven't tested it with the dog yet.
It's not bad, just not what I want for my hallway. The hallway is about 10' long, so if it takes 0.5-1s, you can be all the way at the other end before it turns on. If you are using it for a room where you will be for a while, it will probably be great. I use it now to turn off the lights if there is no movement, where timing isn't an issue, and it is great.
I'm unsure if standard zigbee repeaters work, or if you'd need a special iris v1 zigbee repeater, or if that's not possible---that would be a question for staff.
I've got 2 sensors running at about 70'-100' through a few walls that seem functionally fine. I haven't tested the distance beyond that, yet.