I have to be honest. I just went to the Poly last week for a week...our first visit to the Poly (with 3 stays at CR in the past, but 10 years ago), and honestly, I felt our Poly room was a bit run down and could have been a bit cleaner (dust wise). The bathroom had NO fan, had some peeling paint due to this and just seemed so odd to have a bathroom without a fan to vent the steam. So you had to leave the door open for venting, which adds to privacy issues (esp if you have older kids). Also, not so practical, it had all features in one space (sink, toilet, shower). Our bathroom door lock did not work, and I saw loads of dust on the wall next to our bed, on our nightstand etc. We had peeling wallpaper in our bathroom and a few little broken things in there. Our beds were extremely uncomfortable and the mattresses seemed CHEAP and just not comfortable, even after a day of walking miles. The ac worked good but was SOOO loud it was disturbing to sleep (for me). But DH insisted it stay on...so that was an annoyance to me re the room.
Now for the positives...we loved the resort. Loved the location. Loved the pools. Loved the grounds (OMG, gorgeous). Loved the restaurants, etc, view of castle and fireworks, etc. Loved our room location (tokelau). We had a very big room too.
So would I stay there again? Yes, one day, just for that tropical resort feel and for all the reasons I listed. But we are currently planning an Oct trip and are looking into the WL for a more recent hotel and hopefully nicer room.
However, I originally was debating b/w the GF and the Poly and chose the Poly for the above reasons. I am glad I did and honestly have since crossed the GF off my list for now. We visited there and it just seemed SO stuffy for a family with children. The gift shops closed at 10, it was like a ghost town at night whereas Poly had alot going on, gift shops open till 11 or later, etc.
About the Poly seeming dated....I used to think that. I had visited there many years ago (probably 20 yrs ago) and thought it seemed so drab and dark. I was actually not going to stay there due to this, however, once we did stay there, that feeling went away and the decor and lighting all just went with the theme. So that wasn't an issue (dated feeling) to us.
So I still vote for Poly out of the 2.....but IMO, be prepared, the rooms are def nothing to brag about and certainly not without flaws. HTH