Best product in this space, trust me
For wireless temperature / moisture and water leak monitoring, I've done extensive research (being an engineer myself), bought (not just tried) Honeywell Lyric and two different systems from Ambient Weather. In the end, after 2 years, I ditched all those gears I bought, cut loss, and bought Wireless Tag instead. I only wish I hadn't wasted so much money on those systems earlier.
For temp/hum monitoring, the plug-in sensor with backup battery is the only product in this space to my knowledge. For my use case, which is to monitor my vacation home, this is a must have and there is no alternative. Any sensor purely operating on battery is a maintenance nightmare.
Water leak sensor (indoor use) has also worked reliably.
The only issues I've found so far is with the door open/close sensor. I've yet to figure out how to get it to reliably report and alert a door open situation. Also, the sensor doesn't seem to be able to transmit signal when placed inside a metal mailbox. So my plan to use the sensor (either a REED sensor or a motion sensor) to alert me when my mailbox is open hasn't worked out.
But everything else has worked out beautifully.