I lived in Germany for several years and moved to the U.S. and purchased a "fixer-upper" home. On the docket for replacement were the windows. To make a long story short, the cost of replacing every window on the house with a normal American window was within ~$1k of the price of a single "German" window. The cost to replace all of the windows with the German style was nearly the total price of the home itself.

So yeah, I would love to have those windows, but they're not made or at least readily available in US markets.