I have a Das Keyboard Model S Ultimate and I can vouch for the excellent build quality. Cherry MX Blue switches are loud (and I wouldn't use them in an office), but the tactile experience is immensely satisfying.
At work I have a Leopold Tactile Touch "Otaku" Keyboard (http://elitekeyboards.com/products.php?sub=leopold,fullsize&...). The switches are Cherry MX Brown, which are quieter but not as satisfying. The build quality on this keyboard isn't quite as solid either.
I don't think Das Keyboard Model S Ultimate had a Brown MX ultimate at the time I bought the Leopold or I probably would have bought that. If noise is an issue I also recommend keyboard landing pads (https://elitekeyboards.com/products.php?sub=access,slpads&pi...).
Both keyboards are blank which has made me a better typist. I also enjoy the reaction it gets when people come to my desk.
But most important than anything is the switches. I have cherry MX greens, and I think they're great for typists.
http://deskthority.net/wiki/Cherry_MX_Green
PS: One think you might not like about the Das Keyboard is that their USB models use multiple USB ports for n-key rollover and a USB hub and backlight and stuff like that, or at least the model a friend had did.