I've also had quite a bit of problems with them, I'm currently on my 3rd pair (2100). Apparently, they had issues with their Chinese manufacturer, who consistently screwed up the 'recipe' for the material of the headband. They say that it's now fixed with the latest version of the headphones (2300) as demonstrated here, but they said the same thing about previous versions so I'm still a bit skeptical...
I do really hope they are right though, because apart from this these headphones are just incredible. By far the best headphones I've ever had and worth every bit of hype they get.
Slate customer support is also really quite excellent. When my 2nd pair broke, I received my replacement pair only 4 days later here in Germany from the US.
I was also able to 'fix' my second pair with some tape and a piece of metal. It actually feels way more robust now than an unbroken VSX. Of course you can't adjust the headband any more, but since I'm the only one using them there isn't really a need for that anyway.
Still, it's a good feeling to have these as a temporary backup, in case my 3rd pair breaks and I have to wait for my 4th. At least I can continue working uninterrupted.