Master-Detail grid self referenced

   Hello,
I'm tring to create a master-detail gridview (RadGridview from Telerik to be sincere),
I use Ideablade to catch the data, around 15columns per row, and they're a cartesian product of master detail,
consider for example 

IDMaster, Description, IDDetail,DetailDescription...

public void myMethod()
       {
           IsBusy = true;
           _repository.LoadmyData(18, Data,
                                      results =>
                                      {
                                          var res =  new BindableCollection<myComplexType>(results.Cast<myComplexType>());
                                          var res2 = res;
                                          var comparer = new myComplexTypeComparer();

                                           bool a = comparer.Equals(res.First(), res.Last());

                                          var m = res.Distinct(comparer); //(*)

                                          IsBusy = false;
                                      },
                                     e =>
                                     {
                                         IsBusy = false;
                                         MessageBox.Show(e.Message);
                                     });
       }

  public class myComplexTypeComparer: IEqualityComparer<myComplexType>
    {

        public bool Equals(myComplexType x, myComplexType y)
        {
            if (x.IDMaster == y.IDMaster)
                return true;
            else
                return false;
        }

        public int GetHashCode(myComplexType obj)
        {
            return obj.GetHashCode();
        }
    }

(*) If Res has 3000 items the distinct returns me 3000 items again and it seem's the comparer isn't called... I've read that in order to have .Distinct() working I need my complex type (on google's search  it talks about BusinessObject that implements IEquatable) to implement IEquatable ... what can I do?

Thanks