The smartthings leak sensors are still my favorite. Only $18/ea too. As mentioned before no audible alarm on them, but that is what pushover is for...
I have 18 of them in my house... All sinks, toilets, refrigerator, water heaters, and HVAC dip pans.
My covers blown.
So I take it that you and @steve.maddigan think they are reliable with HE. Some of the Amazon reviews (and other places) suggest that they are not reliable. But of course that can be many factors including ID10T User Errors or poor hub integration. Just curious what actual experience, HE users think.
Never had any problem. I use the device watchdog app, too, so would know if they stopped updating. They never have.
Of course I curate my zigbee mesh carefully. No bad repeaters, no bad bulbs that repeat, lots of good repeating devices, etc, to ensure the mesh stays healthy.
That's always the downside to zigbee... Get one or two bad repeaters and the mesh flops. Technically that would be true of zwave too, but finding a bad zwave repeater is extremely rare. I've heard of zwave bad repeaters, but in 300+ zwave and zwave plus devices I've owned I've never seen one personally.
I have multiple zigbee devices that can kill the mesh, though (all bulbs/light strips). They stay isolated in their own hub.
So this sounds like an additional app by SmartThings... Is that the SmartThings Home Monitor?
Assuming it functions with both HE and the app simultaneously without any issues.
No it is a user app made for Hubitat. Can find it on here with a search.
Here:
I use the Samsung SmartThings water sensors and am quite pleased with them.
That said, if I had existing wiring and sensors already, I'd consider Konnected before replacing them with battery operated sensors.
EH?
Maybe he’s Canadian 
I couldn’t resist.
Yes
I was actually born in Canada but spent my last 35 years in Minnesota so I am a crossbreed.
I bought 10 of these from this ebay seller, as well as other Iris devices from him. I installed 9 of them, and they are awesome. At around $11 each, they are a great buy, all came with the battery and plastic tab still inserted.
They report battery, temp, and wet/dry.
Only 4 left!
I'll argue with @aaiyar and say that it works very well. 
As he said, use @bcopeland's wonderful driver: https://community.hubitat.com/t/release-aeotec-water-sensor-6-w-dock/39292.
I have one with USB power in the dock, and it has performed flawlessly in the short time that the driver has been available. It reports temperature and battery regularly and signals water very quickly. I'll buy a couple more to go in places where I can utilize the combo of the dock, remote probes and USB power.
In battery, no-remote-probe applications, I use Fibaro Flood Sensors. https://www.amazon.com/FIBARO-Sensor-Detector-FGFS-101-ZW5/dp/B01H1M0SP6
They don't get a lot of love on here due to the price, but they are solid. They report quickly and regularly and just sip battery life. Perhaps if I had more of them, I might chase a better value, but overall, the cost difference really isn't that much. I had a non-plus/300-series on ST and it was equally solid, so I bought the 500-series to go on HE and haven't been disappointed at all.
You guys must have money to burn....
$50 sensor (aeotec/fibaro)... $18 sensor (smartthings)... 
I still have 8 old Aeotec (DSB45?) that I converted to being line powered with 3V adapters. Almost 6 years old now. Still fine .....
Works forever ac mains powered and dual sensors
Is it still working? who knows.. Battery will show 100% and be dead.. Do you trust it to tell you there is a leak?
Hey, each to their own. In general, I prefer mains powered over battery too.
My counter in this specific case to that is:
I can replace a **** load of batteries every 2 years for a $30+/device difference.
I am not really that picky about the product. I just want something reliable that works. Burst pipes water damage is one of the biggest category of insurance claims and can devastate a house. So for me, it is worth the money. I looked at the ST first, but some bad reviews really concerned me.
Have you tried multiple probes with them? In other words, I don't really care if the water leak is under the sink or the toilet. I would like to place a probe in each location and get an alert. Obviously a pipe break will alert both, but a slow leak might not. So I really like multiple probes for one device but not sure if you can do that on the ST. I would think any water touching the two points of either probe would set it off but not sure if anyone has tried it. (I understand the probe is not designed for remote probes but someone mentioned soldering probes onto it. Maybe one one top and one on bottom.)
$11 sensor Iris. I have about 75 spare batteries from an auction purchase (Sage Doorbell by the case). They will go bad before I use them all.
No, I just used multiple ST sensors if I couldn't place 1 in a location that would catch a leak from both/multiple sources.
So, for my master bathroom I use 4:
None of them are such that a device w/multiple probes would work/have been close enough to use anyway. Your configuration/geometry may be different.
Guest bathrooms I use 2 in each bathroom:
Kids bathroom I use 3:
Kitchen I use 3:
Laundry room I use 1:
Garage I use 1:
Attic I use 2:
But I don't work for Samsung. Get whatever you want - I have no skin in the game either way. 
I'm just sharing my experience...
In my case there are only 2 places a multi probe would have been practical (without wires draping everywhere - a non starter to me) so the math FOR ME works out as:
With the delta in $ I installed a zwave plus incoming water shutoff valve on the main water line into the house - which is just as important (if not more) than all of the sensors to me.
Download the Hubitat app
