Day-to-day stability mostly depends on a combination of the Zigbee Coordinator adapter hardware/firmware setup, Zigbee devices you add to your Zigbee network and most importantly following best practices to avoid interference + adding enough (well-working) Zigbee Router devices, see these tips → https://community.home-assistant.io/t/guide-for-zigbee-interference-avoidance-and-network-range-coverage-optimization/515752 …if you do all that not buy brand new devices directly when they are first released then you should not have too much trouble regardless of which Zigbee gateway solution you are using.
Before following those best practices I had loads of connectivity problems in the beginning when started to use Zigbee due to interference and too few Zigbee Router devices. Now I advice all to use a long USB extension cable to USB 2.0 port (or USB 2.0 hub) and add at least three “known good” Zigbee Router devices in strategic places around your home before start adding any other devices.