I don't see how anything can be more sturdy than a solid aluminum/metal design that the Pros and Mixrs employ. I'm talking about the Pros and Mixrs only. Could you explain how the headphones you mentioned are sturdier?
I don't rememebr the specifics but I know that they're made in Germany and out of some military-grade or whatever plastic.
There's actually a YouTube video on it, it's rather silly but shows how sturdy they are: "Most unbreakable headphones on the planet? JFB 8.35 D" I believe there's a video out there where it gets run over by a vehicle.
Aluminum is of course very tough, but in real-world cases flexible plastic might be more suitable.