I've stayed at both WL and in a new royal room at POR and have enjoyed them both for different reasons! The royal rooms are brand new and are so enjoyable - lots of details and are all located in the mansions section, so close to the main building. WL, of course is magnificent!
I think, for me, it really comes down to amenities. WL is a deluxe and POR is a moderate, so though I have enjoyed both rooms, WL just offers more (and of course you have to pay for that "more"!) Honestly, they are both great, it just depends on what you are looking for in your full resort stay and not just the room decor.