I have been a Hubitat evangelist for years. My C5 was the backbone of a very well-oiled smart home and had my wife's and kid's acceptance factor. However, after the C8 migration, that has all changed.
My daily schedule now includes resetting many Zigbee devices, this is especially true if the Zigbee device has a battery in it. My wife now laughs whenever I need to get up on a stool to reach a motion sensor that isn't working. The craziest thing is that there seems to be no rhyme or reason to why a Zigbee device falls off the network. I could walk into a room, have the motion sensor pick me up, and then walk out 5 minutes later and the Zigbee motion sensor won't report that motion stopped until I remove the battery and power it back up. This just did not happen EVER with my C5. Something is very wrong with the Zigbee radio implementation on the C8. It took me 3 hours to get my Ikea blinds to re pair with the hub yesterday. They have literally never gone offline on my C5.
The surprise this week was that my once very solid Z-Wave network now can't communicate with half the devices unless I power them down and back up. Even then it's a crap shoot on if the device will rejoin the network. Sometimes the communication is so delayed on the ZWave network that a button push will take 90 seconds to register and turn on or off a device. Craziness.
This morning, I woke up to a nearly unresponsive hub. Apparently, the memory had run out for seemingly no reason. This never happened on the C5 and I have not added any additional automations or devices since the migration to the C8.
I love Hubitat, but the C8 has made my smart home unusable. I can't be the only one who is willing to pay a monthly fee to get these problems fixed. Please, this madness needs to stop.