I'm using a Das Keyboard for two months and it's an incredibly elevating experience. It's so much better than any traditional keyboards that it's hard to describe it with words. I'll write about Das Keyboard in a long post, but I've already made some research to find out whether all mechanical keboards are superior to their dome switch / scissor switch counterparts.
It turns out that the answer is a definite no.
I've heard about / tried the following ones: KPT-102, DTK and Everex. It's not a miracle that you probably haven't heard about anyone of them because they are all crap. Mechanical doesn't mean quality. Apart from the Cherry keyswitches and the original buckling spring mechanism all I see is inferiority.