I like the All Stars. I really didn't like Pop. Lol..I know I'm in the minority on the boards. I really didn't like the one bus stop for a resort with 2,880 rooms and I just really didn't like the vibe. Of course, I was in a room with disco themed wall border and I really don't like disco.

Of course, I think all the sections have the same decor now. And all that being said...I'd gladly go to Pop today if that were my only option.
The All Stars do share buses, but not always. At busier times they will have separate buses leaving the resorts. They are individually smaller and you have the option to walk between them to use the other food courts, pools, or bus stops. In fact in some cases you may be closer to another All Star main building/bus stop than the one you chose to stay at. I know that sounds weird, or maybe inconvenient, but it actually works out really well.