Previously found at https://www.ozbargain.com.au/node/775342, but seems to be back in stock. Personally I have bought a few of these kits the gateway is good as a night light. [Update - seems this version gateway does not have a light, but on the flip side might also support bluetooth sensors] Not sure if these are the Australian model [Update - seems that this is most likely an Australian version], but if not then (unless you can get the key for local access eg via https://github.com/PiotrMachowski/Xiaomi-cloud-tokens-extrac… and https://github.com/rytilahti/python-miio) if you want to use the gateway then you need to set up the Xiaomi app with an account in the Chinese mainland (don't need a vpn or anything like that - you just say you are in China). Overall it's a cheap starter kit for people who want to start to play with home automation, using perhaps the button as a door bell and the door sensor to alert you if the door is left open for too long. It would perhaps be better if it included a power switch or light bulb so you could use the door sensor to - say - turn the light on in a room when you open the door but it is a start.
Anyhoo, I just use the (Zigbee) sensors in combination with a Sonoff ZB Dongle-E and Home Assistant so even if you toss the gateway away it still ends up as just $10 for each sensor (remote button, temp/humidity, and door) which isn't too shabby.
Can you explain the night light comment re the hub?
I have a few of these but didn’t realise that’s as an option.