Old clamp broken then I replaced it with new type. That broke to. But they did get a lot of use.
Newer clamp works better and offers some reduction in stress to the frame due to its taller design.

Birdie is great, but I see it as a very different bike to the mezzo.
Mezzo is a "train" bike, whilst a Birdie is more of a bigger "car boot" bike.
My Birdie still has some of the small wheel handling issues, But I believe these are reduced if you have some forward reach on the stem? I might fit a Dahon Adroes extender to it.
Not had birdie long. And it still needs a few details sorting out. I have always wanted one, but I only work part time!!

Birdie is a softer ride, lighter bike, bigger to ride and fold, a bit bouncy, sometimes feels quite fast, but it feels mainly like a full suspension bike.

Both Shocks can be stiffened with different elastomer,

Some people use Birdies on the train, I no longer commute on train daily, think I would tend to opt for my fast black mezzo usually. But if meeting friends for pleasure ride I would take the Birdie.( Or use my Mezzo suspension seatpost option?)

I post some comparison photos in a couple of weeks