It's amazing _but_ do NOT use a raspberry pi to run it. Save yourself a ton of headaches and buy a mini pc (there was a list of used mini pcs posted here yesterday from ebay). Also I recommend using HAOS (or whatever the "we install and run the whole OS" option is called) so that you can use things like plugins without messing around with docker. I love docker but trust me, life is easier on HAOS.
I liked HA but felt like it wasn't really "stable". I used a Pi 3 for a while, then a Pi 4 decked out (highest ram, NVME storage, super nice case, etc) and still felt like it was unstable. I chalked this up to HA but then rolled the dice on a Beelink mini pc and it has been rock solid ever since. Also don't be misled by the lower price of the Pi, I paid more for my Pi 4 setup than the Beelink (or about the same).
I blamed everything from the Zigbee/Z-wave dongles, to HAOS, to HA itself, etc but in the end it was RPi. The 4 was the last Pi I'll ever buy.
EDIT: I was in a hurry and didn't add my normal disclaimer when I talk about the RPi's:
Yes I know some of you have a Pi 1 that been running you entire life since it first came out and you think I'm full of crap. I've owned every Pi 1-4 and never been truly happy with them. I bought them "raw" and sourced all the parts myself, I bought high-end (at least in price) kits with everything included, I bought all official accessories (like power), they always were just that little bit unstable.
It would work great for days/weeks then randomly not be reachable (wired or wireless). I spent just shy of $200 for my last "builds" which included a NVME drive (240G, lest you think this is where the cost was), RPi case, RPi NVME hat, RPi 4 8gb model, SD card, power, etc and the result was still instability. I don't know what to tell you. Maybe I'm a moron but my experience with them has not been great. That said I want to love them and I loved my RPi 1B even with all it's warts, a $35 "credit card sized" computer was awesome. Maybe I just don't want to tinker as much anymore and value stability.