Well you certainly have a dilemma! We have stayed at both and I can give you some things to think about.
The WL is a relaxed laid back atmosphere with rocking chairs rustic decor with
beautiful flora but whispering canyon gets really loud In The lobby. It is possible to get glimpses of wishes in certain areas. Artist pointe is a signature restaurant with some really awesome mussels. The buses make it difficult to just jaunt back to the resort for a nap or a swim.
The poly is über relaxing laid back atmosphere.. Rooms are extra large, the pool is absolutely gorgeous! You can be back at the resort from MK or Epcot in about 20 minutes there or back. Sitting by the pool sipping a Lapu Lapu as the sun sets is something that is heavenly! Waking up early nursing a fresh cup of coffee from the 24 hr captain cooks while walking along the totally vacant beach as the sun rises! Hearing the faint sounds of the cast members at MK getting fired up for the day.. Priceless! Sitting on the beach watching the castle change colors.. Fabulous! Did I mention WISHES from the beach? It's a head on view. The reflections on bay lake as the fireworks dance in the night sky cannot be discounted! The smell as you walk leisurely walk through the tropical rainforest lobby.
Not being biased or anything..
Fuzzy photo from the poly beach
Good morning poly!