Using 3rd party components for WPF applications

I did a small review of available components suites for WPF. I focused mainly on grid and charting controls, as the nature of WPF allows customization of the UI in ways that previously required 3rd party components in a Winforms development:

Xceed:
Grid control only
Express edition - Free
Professional edition - 500$
With source code - 1250$

Infragistics:
Netadvantage for WPF
Includes DataGrid, Carousel controls, Ribbon, Chart, editor controls (masked edit, datetime picker, etc)
Price - 800$
Source code not included

Component One:
Studio for WPF
Includes DataGrid, Chart, Report viewer, Schedule controls (datetime picker, calendar, scheduler)
Price - 800$
Source code not included

Syncfusion:
Essential studio WPF edition
Includes Chart, Docking manager, Ribbon, Groupbar, Taskbar, Datetime editor, Autocomplete textbox, Font listbox, Color picker, numeric updown, masked edit, Tree view
Currently no grid is available
Price (with source) - 600$

As you can see, there aren't many options available at the moment. What is worse is the fact most tools don't come with a source control, meaning using them means taking a risk of losing support in the future.

My recommendation: Don't purchase anything unless you absolutly need to. The only thing worth considering purchasing at the moment is a charting control (as there is none from Microsoft), but you should also consider an open-source solution.