Pop is my favourite value, but I love CBR much more! The moderates are a big step-up from value resorts, IMO. We like the queen beds, the newly refurbished rooms, the TS dining option, the beautiful grounds, the tropical island atmosphere, the great pool area, the hammocks, the extra quiet pools, and the extra space in the rooms. With the ages of your children, i believe that CBR preferred would be perfect!
Of course, we don't mind the bus stops around the resort. I actually like thee extra stops as it means that no rooms are very far from a bus stop. Once we are on the bus, we don't mind a few extra minutes, but that is only our opinion, and many people find this an issue. If a single bus stop is more important than the CBR advantages listed above, then Pop might be the better option for you.
Either resort is really good value, though, so enjoy which ever you choose!