I've been using it for about 6 months now and I'm mostly happy with it, but there are definitely some pain points. Depending on individual use-case, it can be a bit tricky to get setup.

I dislike Docker Desktop for Windows, so I run it in a docker container on Windows Subsystem for Linux with Tailscale and have configured it to automatically initialize all of it when my PC is powered on. It took me many hours and lots of chatting with GPT to get it working. Perhaps my configuration is uncommon though.

My biggest issue with it is the overhead and lack of smart configuration. For example my wife and I have the same mobile device (Android) and we can't share an account while having backups made at the same time because backups mimic the default android images folders and both devices have the same structure. If we have two different accounts, then each account generates its own thumbnails and you have to run facial recognition on each one individually (which required a lot of manual tagging). This wastes a lot of time and space.

The second problem is it can't just work with the file system structure and organization I have in my external folders "as-is". You basically have to recreate them as albums inside immich yourself. I found a handy script that did this for me, but the experience is somewhat lacking.

Third issue is I can't backup to external folders. Backups go to the default immich folder and I have to manually pull them out of these and dump them in the correct external folders (recall that I have my own file structure).

I've gone to their github and luckily there are issues out on all of these which I promptly upvoted, but I'm not sure any of them have been resolved by the team yet. I'm hoping they get fixed soon.

Edit: I should mention that I don't enjoy having a bunch of different services running to get this working like an out-of-the-box experience should. For example adding Dropbox to the equation is a no-go for me. The idea of adding even more system resources dedicated to this function is a huge turn off. I also use a cheap DAS (not a NAS - and yes I do manual backups for offsite storage) because I don't want to fork out a fortune for the Synology solution. These are all things that Immich itself should be able to handle without having these complex systems with multiple failure points.