i've not been impressed since gpt3.5
They tend to poke the free ChatGPT for ill defined requests and come away disappointed.
The nice part is I can spend an hour or so writing specs, start 3 or 4 tasks, and come back later to review the result. It's hard to be totally objective about how much time it saves me, but generally feels worth the 200/month.
One thing I'm not impressed by is the ability to review code changes, that's been mostly a waste of time, regardless of how good the prompt is.
If you're not using AI for 60-70 percent of your code, you are behind. And yes 200 per month for AI is required.
That's a low bar.