I worried about Pop too because we never stayed at a value before. While we only spent one night there, then moved to another resort, we enjoyed our short time there very much. If it makes you feel any better, while I am debating on whether or not to go to WDW this fall, my two choices are Pop and POR. Lots of bang for your buck at Pop, imo.
Since your original question was what didn't we like, I can only say that while the icons are great fun and DGS (age 6) absolutely LOVED it there, here are the only very minor minuses about Pop for me:
1. I was thinking for a 6-7 night stay it is a lot of concrete and tall buildings to look at, more so than a peaceful, beautiful, landscape. It has more of a busy city feeling than a "enjoy the landscaping getting away from it all" feeling. However, when we were there just after Thanksgiving, it was not at all noisy or crowded.
2. For a longer stay, it might bother me that the rooms are small and ours was dark since it only has one window. But how much time do you spend there anyway?
3. No counter space for toiletries, but I'm not sure if the mods have sinks with counters either. Again, a very minor inconvenience that can be fixed with an over the door shoe hanger for the rack next to the sink.
These little things would not stop me from staying at Pop by any means. When they say value, they are not kidding, because it was well worth the price. I was very impressed for the money and we are used to staying at Poly. Staying at Pop made me realize we were spending way too much money staying at Poly.
We stayed in the 50s building facing the lake. Great location. DGS and I actually had fun looking out across the lake to the Legendary Years. We imagined it was haunted and I taped him doing a "documentary" on that subject...lol.

He still talks about that. Have fun!
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