My experience has been decent. I don't know that it has truly saved me much time but I can understand how it FEELS like it has. Because it's writing so much code (sometimes), it's hard to vet all of it and it can introduce subtle bugs based on faulty assumptions it made about different things. So, it will dump a lot of code at once, which will get me 90% of the way there, but I could spend an hour or two trying to nudge it to fix it to get it to 100%. And then I will probably still need to go back and reorganize it, or have it go back and reorganize it. And then sometimes it will make small adjustments to existing, committed code that will subtly break other things.
Something that has surprised me (in hindsight, it isn't surprising) is that sometimes when I feel like it misunderstood something or made a faulty assumption, it was actually me that had the misunderstanding or ignorance which is humbling at times and a good learning experience. It is also pretty good at bug hunting and DEFINITELY very good at writing unit tests.
I count myself as pretty lucky that this domain seems to be very well covered in training. Given the law of averages, most people's domains will probably be covered. I'm not sure how it would fare with a niche domain.
This is roughly my experience as well. The AI is great at the first 90% of the work and actively counterproductive for the remaining 90%