That is a derived CheckBox that is meant to be used within the template of the xamCheckEditor. It has some overriden members specific to use within the xamCheckEditor to adjust behavior.
The xamCheckEditor was designed for use in the embedded case (e.g. hosted in a field of the xamDataPresenter). With regards to the Text property, that is defined by the base ValueEditor class. The Text and Value properties are integrally linked; the Text is a string representation of the Value and the Value is an instance of the ValueType for the specified Text. So in the case of the xamCheckEditor the Text property is a string representation of its boolean state - it is not a label. Currently, since the editor was designed for embedded use, there is no property exposed that would serve to provide a label/content that would be adjacent to the check editor. You may want to submit a suggestion for adding this.