I have no direct experience with this new device mentioned in OP (SLZB-07) but I have been using their model SLZB-06 device since July (about 6 months now) and it has been operating flawlessly (as far as I can tell) and I am very happy with it. I am currently up to 37 Zigbee devices, and adding more all the time. Anyway, they seem to make nice hardware which is reasonably priced, so I thought I would share my experience. (source: https://community.home-assistant.io/t/smlight-slzb-07-zigbee-coordinator-usb-dongle-based-on-silicon-labs-efr32mg21-20dbm-radio-soc-mcu-9-98-launch-promotional-price-shipping-otherwise-14-99/625431/37)