My experience has been that the laundry service is OK if you need it but nothing special. They do not use fabric softener or whatever else makes the clothes smell fresh and clean. It's just a basic wash and fold good for Tshirts or underware but not really suitable for nicer clothes.
Unfortunately all ships do not handle Platinum debark in the same manner. Some will actually escort you off the ship first while others just lump Platinum Members in with the self-debark people and don't seem to care that you do not get priority debarcation.
8 Norwegian: Sky, Jewel, Dawn, Epic, Pearl, Breakaway, Getaway, Escape
11 Windjammer: S/V Legacy X3, S/V Polynesia, S/V Caledonia, S/V Diamant, S/V Sagitta X2 S/V Mandalay X2, S/V Vela
HAL Statendam, MSC Divina