Most of our Pop busses were fine.
We just returned 4 weeks ago from our stay at Pop and it was indeed nice to have a dedicated bus line. We didn't find that the Pop location with the bus was any worse than any other place we went to via bus.
95% of our buses were fine.
If you know how close Wilderness Lodge is to the Magic Kingdom, then you know how nuts it is that it took 45 min. to get a bus from the bus stop at MK to drop us off at Wilderness Lodge. We could have walked it in 20 min, even with the shorter legs of the 7 and 5 yr. olds with us.
It took us the same amount of time (45 min.) most nights to get back to Pop from the MK or Epcot or vice versa, even though MK is further North. Go figure.
Keep in mind, we did our best to be the last ones out of the park, thus minimizing the throngs of people at the official park close time. I highly suggest it.
One night, I really think we were the last guests in Epcot. There wasn't anyone else to be seen. It was so cool.
For planning purposes, people here have said it before (Belle!), plan on 1 hr. to go from one hotel to another or to park hop and you should be fine.
1 hour may seem like a long time, but if you plan for it, it's really no big deal.
Just don't be at Spash Mtn and expect to be at LeCellier in an hour. I'd put that trip at 1.5 hours if everyone in your party walks very briskly the whole time.
We did have some bad experiences bus-wise when we were put on a bus that wasn't clearly Disney owned, or was a Disney Cruise Line bus.
On the non-Disney bus, we were put on that in the middle of the day from the Pop Century Bus Stop, only to be dropped off in the middle of the far bus parking lot at Epcot , nowhere near a curb. We asked the bus driver why so far away and he said since he was a non-Disney bus, he wasn't allowed to drop us off where the Disney buses did. Funny that he could pick us up at the Pop bus stop for Epcot,though. It was a dangerous walk from the parking lot, having to dodge 2 other buses crossing in our path. We did complain to the little bus desk at Epcot, but were told that Disney ran out of buses and needed to contract out. Ran out of buses in the beginning of October!?
The Disney Cruise Line bus didn't know where to drop us off at MGM, so we ended up circling the parking lot twice until the driver found a castmember to give them directions to the proper bus stop. That wasted about 15 extra minutes and was supposed to be the first bus of the Day to MGM from Pop. It ended up being the second, since we arrived just after the second bus from Pop did. We know this because of another couple we recognized from POP who saw us get on the first bus, while they waited for the second. That was very strange.