It's always a challenge when you know a developer's heart is in the right place, but the software needs work. Do you leave honest feedback and potentially hurt their sales, or do you stay silent and hope they can pull it together?
I think Stunning's heart is in the right place. But the software is currently weak. It keeps producing basically the same ungainly starter site for me, design-wise, no matter what info I give for the initial prompts (a little or a lot of detail). It doesn't understand color contrast (legibility issues). Layout options are primitive.
IMO, it needs different "modes". It needs a "pro" mode for if you do have good copy, because you can't tell the builder where to put your existing copy, and it has a (small) mind of it's own. And yes, I know you can go back in and change everything, but then you might as well be using Wordpress.
And really, if you need the "done-for-you and write it all for you" mode, should you be building a website at all? Because what you get is so generic that it won't serve you well.
Plus, it's a locked box, so you can't expand beyond the functions that Stunning offers, and your ability to embed outside features is limited for coding and security reasons — currently.
So this is something to buy and hold, and hope. Because I can't imagine using it for anything production-ready at this point.
I thought I might be able to use it as an idea-generator, at least for now. But I'm not liking the outputs it produces at this stage. YMMV. (sorry folks)