Leslie,
No matter where you read you'll find lovers and haters of each resort, so don't stress too much about any negative comments you may read. Pop Century is actually the first value resort I would recommend. The bus system there is efficient - more so, in my opinion, than at the other value resorts.
There is only one bus stop at the resort, which can be a positive or a negative, depending on how you look at it. It's nice to not have to wait on a bus while numerous other stops are made, but it can also be tiring at the end of a day to walk from the one bus stop back to your room. If that's a concern to you then you can upgrade to a preferred room location. The main difference between the buses here and those at the All-Stars is that Pop Century always has their own buses, whereas the All-Stars often share, meaning more stops and more time spent traveling. Also, because Pop is so large and so popular, there are always a lot of guests staying there, which means more buses running. When we use buses from a deluxe resort we often have a longer wait because fewer guests are staying there and using the bus service.
I'd advise you to plan ahead and allow yourself time to wait for a bus, just in case the crowds are thick. If you have a dinner reservation or something important that you're on a time schedule for, then plan accordingly and allow yourself an hour to get there. You will not be likely to need that much time, but definitely better to be safe than sorry later.
I really don't think you'll regret staying at Pop. If you look at the resort reviews on
www.allearsnet.com you'll see that their readers have ranked it the highest of all the value resorts. Maybe that will make you feel better about your decision as well. And remember that no matter what, any day at Disney is a good day! :)
Have a great vacation!