We were at POR Alligator Bayou for 10 nights in Aug. One night, we heard our upstairs neighbors (jumping around?) and only once or twice, we had the background noise (it was faint) of someone's TV. But, that was it as far as noise goes for our whole stay. We thought that it was a pretty quiet resort! And, we hope to stay there again.
We are not used to double beds, but other than the size (which came as no surprise), the beds were comfortable. Dd used the trundle bed and said it was quite comfortable.
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An aside on noise........one of my friends went to ASMu last month. Because of the free refills with the refillable mug, they let their 8 y.o. boy have tons of Coke. He had a major caffiene and sugar high in their room--doing cartwheels, bouncing all over the place, etc. And, he is a BIG boy for his age. Can you imagine being beneath them?!

When it comes to noise from neighbors, especially the ones above you, I think that it's luck of the draw regardless of where you stay with how much noise you'll get. The one night we had upstairs noise was when it sounded like a family with kids were letting the kids jump from the beds. That could happen at any resort.