I've been playing around a little bit with Telerik's RadControls for Windows 8. If you haven't checked these out, they're worth your consideration. The package, which supports both HTML and XAML, include chart, gauge, hub tile, slider, auto complete, combobox, date picker, drop-down lists, numeric box, time picker, and pagination controls. I mention this now because they're offering the whole package for $399 during February, and the price increases $100/month until it reaches the full price of $999 in August.