I have stayed at the Poly 4 times, 3 times were each a weeks vacation, (One of those weeks being my honeymoon), the other was a one night stay.
Last year we stayed at CSR for a week and we took a sightseeing tour over to the Poly to see the new pool. Well, the Poly looked like some kind of third world country, there were people EVERYWHERE!!! The pool was so crowded people were walking around looking for lounge chairs then just leaving. It seemed like there was trash everywhere too. The GCH just didn't seem to have the ambience it had when we used to stay there. I looked into the little snack place, (Captain Cooks?), and it was an absolute nightmare, food all over the floors, trash everywhere. This was during slow season.
If I had my choice I'd stay at CSR over Poly any day. My reasons for that probably have nothing to do with any of the above though. We just really liked CSR, we liked the full service restaurant, the Pepper Market, we like hot tubs and they don't have one at the Poly. I liked the pool and pool bar better at CSR.
I'm also not too crazy about the interior hallways at the deluxes, I think they lead to MORE noise with kids running, ADULTS SHOUTING in a confined space, etc.
I can't say I like all moderates better than deluxes, I just like CSR better than the Poly.