DropDownList in RadPropertyGrid does not trigger PropertyValueChange event after Value is changed by user

        public RadForm1()
        {
            InitializeComponent();

            Item item = new Item(123, "Title", DelivertType.PickUp);
            this.radPropertyGrid1.SelectedObject = item;

            this.radPropertyGrid1.PropertyValueChanged += radPropertyGrid1_PropertyValueChanged;

            this.radPropertyGrid1.EditorInitialized += radPropertyGrid1_EditorInitialized;
        }

        private void radPropertyGrid1_EditorInitialized(object sender, PropertyGridItemEditorInitializedEventArgs e)
        {
            PropertyGridDropDownListEditor ddlEditor = e.Editor as PropertyGridDropDownListEditor;
            if (ddlEditor != null)
            {
                BaseDropDownListEditorElement element = ddlEditor.EditorElement as BaseDropDownListEditorElement;
                element.SelectedIndexChanged -= element_SelectedIndexChanged; 
                element.SelectedIndexChanged += element_SelectedIndexChanged; 
            }
        }
         
        private void element_SelectedIndexChanged(object sender, Telerik.WinControls.UI.Data.PositionChangedEventArgs e)
        {
            BaseDropDownListEditorElement element = sender as BaseDropDownListEditorElement;
            element.SelectedIndexChanged -= element_SelectedIndexChanged; 
            this.radPropertyGrid1.EndEdit();
        }

        private void radPropertyGrid1_PropertyValueChanged(object sender, PropertyGridItemValueChangedEventArgs e)
        {
            this.Text = e.Item.Label;
        }

        public class Item
        {
            public int Id { get; set; }

            public string Title { get; set; }

            public DelivertType Delivery { get; set; }

            public Item(int id, string title, DelivertType delivery)
            {
                this.Id = id;
                this.Title = title;
                this.Delivery = delivery;
            }
        }

        public enum DelivertType
        { 
            PickUp,
            Delivery
        }