I was part of an investigation which considered Coherent products for one of the Forza titles. We didn't go with it at the time, and I haven't had the opportunity to use it on a title at other companies, but it looks rad.

Forza used a custom UI system based on XAML and the acrylic elements at the top of the article were largely implemented in a custom shader. For a custom system it was pretty solid. We also built a lot of tech into it related to 3D placement of elements to support diagetic UI.