I had this same issue with RadGrid, which appeared to have been fixed in 0422 2010.
I am encountering the same issue in RadComboBox now i am using this instead of a grid.
If RadComboBox is bound to a observable collection, and there is a change to an item in the collection (ie replace an object in the collection), the RadComboBox SelectedItem property points to the old instance of the object that was in the collection.
Also if an update collection event occurs, the displayed/selected item, does not seem to update. Eg. Combo box displays Person names collection. Another textbox modifies the name, INotifyPropertyChange is generated, then CollectionChange event is generated, but combo box displays original value.
Work around is to externally catch the collection change/update event and update RadComboBox SelectedItem to the new object instance.
I am encountering the same issue in RadComboBox now i am using this instead of a grid.
If RadComboBox is bound to a observable collection, and there is a change to an item in the collection (ie replace an object in the collection), the RadComboBox SelectedItem property points to the old instance of the object that was in the collection.
Also if an update collection event occurs, the displayed/selected item, does not seem to update. Eg. Combo box displays Person names collection. Another textbox modifies the name, INotifyPropertyChange is generated, then CollectionChange event is generated, but combo box displays original value.
Work around is to externally catch the collection change/update event and update RadComboBox SelectedItem to the new object instance.