I’m not running them on Zigbee, I’m running them on Bluetooth using the Home Assistant / Nabu casa bluetooth protocol for sensors - BT Home.
Never had a problem with them - I have 10 now.
EDIT:
An ESP Proxy is any ESP32 device running ESP Home that will operate as a proxy sending raw bluetooth packets directly to Home Assistant over the network, so you can place them nearer to the actual bluetooth items that you want to talk to.