It did a great job. It mapped out a reasonable trip with my having a rental car. This was just high-level (e.g., 2 days here, 3 days there, 2 days there, 1 day there). But I gave some refining instructions, and it took less than 30 minutes to plan a trip where, in the past, it would take a lot longer to map something like this out.
I'll use ChatGPT to dive deeper (e.g., "what should I do each day in X").
I also have travel books that I'll use, but it's so much easier to have a framework that makes total sense with little effort on my part - and no travel agent.