Yes, devices will automatically pick the “best” route. That may not be what you think is the best route though. For example, a device with a strong signal to a router may still communicate directly.
No need, and Heal is more likely to be harmful than helpful (Z-Wave Plus devices will learn the best route over time, when you Heal them you cause that knowledge to be wiped and they start again).
Did you end up buying one and did it extend your signal?
I’m also looking into extending my Xiaomi Mesh. I have a few sensors that is on the edge and doesn’t update as often as wanted. So I was wondering if I could go with this or if I should buy a second Gateway.
I already had two of them, but was wondering about how they work.
It seems to work better now that I re-added the devices is question, close to the plug.
Did some tests with the zigbee USB stick, but it seems a bit to flaky for my liking, so I will keep using my Xiaomi gateway.