Just for giggles, I had the wife by me a Das Keyboard II for my belated birthday present. That's the one without labels and the clicky keys.
The keys are nice, but it feels wrong without the same weight as the lead lined 30lb. Model Ms.
Aside from that, I'm using it on top of my laptop for a while. It's odd. I'm ok as long as I don't think about there being no labels..otherwise, all hell breaks loose.
I also think it's odd in that I don't know where the letters are if I think about it...my hands just know where the words are. Go figure.