I'll be sure to post my feedback. Cobblestones will probably have to wait for my return from vacation.

The Ultralight is not the lightest, but it's okay. It's light enough for my purposes.

I liked the Birdy when I tested it. It's too wide when folded though. I might buy one someday.
If I'm not mistaken, I read somewhere that the new version will be released in 2025.