Hello everyone, there is no thread to talk about Apple Homekit so I started one.
I almost completed my Apple Homekit connected home that I wanted to do since a while (pending parents approval haha).
This is the post to thank you people who shared their previous experience here as a reference for me.
My house is about 4000sqft and for the Homekit Accessories I have about 30 Terncy Wall switches in the house, 25+ Philips Hue Lightings...and multiple Terncy Door Sensors, 3 Yeelight bedside lamps, 4 Apple HomePods, 1 LG B9 OLED TV.
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The responsiveness you seen is DUMB light + Terncy Switch. I think the contribution factor is there is no compromise of connection between the hub and my home network - via ethernet. And Terncy optimisation. I don't have Aqara switches at my place, so I can't really speak for Aqara but before I bought Terncy I had tested the Aqara ones at my friend house - and Terncy is significantly faster, as my friend just bought 2 of the Terncy ones to replace his broken Aqara switches. Aqara uses the 2.4Ghz spectrum so I think it depends on your area whether there is a lot of interference or not - if there's no interference I believe it would be quite responsive as well.