Aeotec Z-Stick 7 vs Sonoff Dongle Lite MG21

The Sonoff Dongle Lite MG21 is the better overall dongle for most buyers, since it does Zigbee and Thread, carries a stronger amplifier and a higher owner rating, and costs less. The Aeotec Z-Stick 7 wins only when you specifically need a Z-Wave controller, which the Zigbee/Thread MG21 does not provide.

Protocol. The Aeotec Z-Stick 7 is a Z-Wave 700 controller only, while the Sonoff Dongle Lite MG21 is a Zigbee 3.0 coordinator (and router) that can also be flashed as a Thread border router. They do not overlap, so the devices you want to connect decide which stick fits.

Only the Sonoff Dongle Lite MG21, which is a Zigbee coordinator and router with a +20 dBm amplifier and a +3 dBi external antenna, so owners run extra units purely as routers. The Aeotec Z-Stick 7 is Z-Wave only and cannot route a Zigbee mesh.

Buy the Sonoff Dongle Lite MG21 if you want an affordable, versatile Zigbee coordinator (with optional Thread) for Home Assistant, Zigbee2MQTT or ZHA, or a cheap Zigbee router to extend coverage. It ships set up for Zigbee, so plan a flash if you want Matter over Thread.

Buy the Aeotec Z-Stick 7 if your smart home runs on Z-Wave and you need a dependable Z-Wave 700 controller for Home Assistant, openHAB or ioBroker. Expect to update its shipping firmware before adding devices, and remember it does no Zigbee or Thread.