We just stayed at a Poly studio with the 4 in our family. Sleeping arrangements were perfect, as long as one of you is smaller (under 4'). Plenty of room. We didn't feel on-top of each other at all. Felt we had plenty of room when the beds were all down. The balcony was nice too - plenty of room for 4 people to watch the fireworks every night.
Loved the 2 bathrooms for 2 sinks for the morning or nighttime brushing teeth, doing hair, shaving, getting ready, etc., but we really would have liked 2 toilets instead of 2 showers. The 2 showers were unnecessary. We never showered at the same time. But coming back into our room, all 4 of us needed to go to the bathroom at the same time, and we couldn't do that.
We wish the kitchenette was a little larger. Even one more mounted cabinet would work so much better to store cereal and snacks. We had to use part of the closet for that.
Looking forward to a 1BR with full kitchen in the new Poly towers next year. But, the location of the Poly studios to the Transportation and Ticket Center to get to Magic Kingdom and Epcot is sooooo convenient, we'd lose that with the tower. But, really glad we chose to buy at Poly.