I don't. I've never seen the HR23 do a random reboot, but since the blue ring is off I'd know if it did. The HR24 seems to be well behaved. I also don't worry about random reboots due to power drops as both are on UPSs.
Being on a UPS doesn't seem to make any difference, my 20-700s still occasionally reboot for no apparent reason and they're on UPS devices.