If the POLA Regulator parts PTH12050WAD and PTH12050WAH are now mechanically and electrically "equivalent' why does TI still offer both options ? Producing both versions must have a cost associated. Is there an advantage to offering both of these versions? I understand that up until 2006 the PTH12050WAH was non-RoHS, after it was updated to become RoHS certified, both parts are now the same?