It would be more convenient to the end user to have a single checkbox in the header of RadListView(DetailsView) which will check/uncheck all the items in RadListView. Also, the group items should have a checkbox which checks/unchecks all the items in that group.

Add StartsWith  autocomplete mode as in the RadDropDownList.

Currently, when you edit the Columns collection of RadListView, you cannot change the Name of the newly added columns.

It should be similar to RadCheckedListBox:

DataTable dt = new DataTable();
dt.Columns.Add("Id",typeof(int));
dt.Columns.Add("Name", typeof(string));
dt.Columns.Add("IsChecked", typeof(int));

for (int i = 0; i < 10; i++)
{
    dt.Rows.Add(i,"Item"+i,i%2);
}
this.radCheckedDropDownList1.DataSource = dt;
this.radCheckedDropDownList1.DisplayMember = "Name";
this.radCheckedDropDownList1.ValueMember = "Id";
this.radCheckedDropDownList1.CheckedMember = "IsChecked";

The user won't be allowed to enter some text if a match doesn't exist.