Haven't tried it yet, but I can see myself using it in the future. It could be great for automating Mac/iOS development and administrative workflows. I don't think you can compile, sign, notarize, or inspect Mac/iOS apps without Xcode tools (which are, of course, Mac-only). It's a pain in the ass to operate Mac VMs for such purposes, and it's only getting more difficult as time goes on. IIRC Apple only allows 2 guest VMs per host now.
Not sure if there are any non-Mac tools to work with dmg files (Mac disk images).
If GUI support is sufficiently developed in the future, there are plenty of Mac apps I would like to run. iPhone app support on Linux would be an absolute game-changer.
It took an hour or two to compile and takes up about 5GB of space. The only program I'm really interested in is Xcode, which doesn't work at the moment.
Safari is by far the best browser for battery performance. I'm uncertain if this would translate over to safari running in darling when it supports guis fully.