I have stayed at all 4 (POP, ASMu, ASMo, and ASsp) rooms are the same, theming is different, food courts for the most part offer the same, there 5 sections, the Grill, the pizza shop (also has pasta) cold foods, specialty foods (this where you will find the differences), final section is ice cream shop and sweets. I've recently read that Pop has had to share buses with AoA in the morning.
For me I prefer All Stars. We take our car sometimes to the parks or if we are eating off site or if DD19 wants to hop over to McDonalds, there's one just outside the guard gate to All Stars. Parking at All Stars is just better and closer to the rooms. Again something we prefer. Plus I like less rooms, each All Star has 1,920 Pop has 2,880.
When are you going? ASsp's food court will be closed for refurb between August to December. Supposedly the will have Motor coaches to take people to Music or Movies but it is a hassle to consider.
I'd visit Allearsnet to view menus and see pics of the rooms and resort layout.