Phoenix Sky Harbor has been my departure and final destination a couple times, but I've most been here for layovers.
To me Sky Harbor defines the idea of an airport. It's fairly convenient, always crowded and very spread out. It's not interesting in anyway and basically serves it's purpose. Sunday nights are an especially busy time that I've had layovers at Sky Harbor. Many business travelers make their weekly commutes through Sky Harbor and the crowds are big as a result. The plus side of this is because the fact that this place gets so much traffic, there are lots of amenities and places to grab food and drinks. I've never had trouble finding a coffee or a magazine in any of Sky Harbors terminals.
I'd say one of the bigger drawbacks are the airport's small gate sizes and lack of seating. I always see tons of people packed around the gates with nowhere to sit down before their flights. All in all though, Sky Harbor is a decent airport, especially if Phoenix isn't your final destination.