Design wise they're very similar to something like a cetus, or many other Chinese printers with similar mechanics with a major difference: Smooth rods and bearings instead of linear rails.
In my own designs I've pivoted away from rods in favor of rails and seen much greater quality, accuracy, repeatability, and speed, even with cheap knock off rails from China, and most of the industry is moving that way as well.
What's curious is you can get a machine similar to the mini, using linear rails, and more metal or injection moulded parts over 3D printed parts, for just a little bit more than the mini.
Prusa has quite a good reputation though, so I'm skeptical they would release an inferior machine at a the same price point, so like I said, really curious to see how well these works.