IKEA's whole smart home ecosystem is presently being overhauled from Zigbee to Thread/Matter, with a product availability gap in the meantime.

https://www.ikea.com/global/en/newsroom/retail/the-new-smart...

Personally, I find their contact sensors (the tall-ish thin ones) to be quite unreliable. I live in a modest home with plenty of zigbee devices as repeaters nearby and the contact sensors often stop reporting at random. I’ll pop it off the door, click repair on my coordinator and then hit the reset switch on the sensor; back online.

I like them because they can use rechargeable AAA batteries but if I still have to touch them every few weeks to repair, I’d rather switch to a different brand that is more reliable and uses less ideal battery formats.

That said, the newish Inspelling plugs in the EU market are fantastic. They report reliably, can handle larger loads, and cost about €10. For that price, it’s hard to complain that they are a bit larger than other options.