We loved the ship. We are the type to eat early, and go to the Princess Theater to see the entertainment most nights. Of the eleven evenings on the ship, they had something new on 9 of them, and we saw 8. We loved most of them. Excellent: Scottish Violinist, Welsh singer and comedienne, the ships own singers and dancers (esp "Once Upon a Dream" show). Very good: Comedian guy. Fair: Magician.
Loved "movies under the stars". Nothing like floating along under a beautiful full moon, watching a movie on a giant screen, and the ship people come by offering (free) WARM cookies and milk. Unbelievable! They would also go around about 3:30 every afternoon with warm cookies and (cold) milk.
We had anytime dining. Between 5:30 and 6:30, walked right in every time. When we walked out ~7:15 - 8:00pm, the wait looked to be 5-7 minutes or less. Excellent food, and lots of choices every night. I went hunting for more food at about 10 pm :) and they have a theme buffet near the stern of the ship every night. One night was German night, WOW. The pizza is excellent, and the grill is great (fries, hamburgers, brats). The buffet is great. We never had trouble on this cruise finding a seat. Last year in the Baltic, it was much more crowded at times. I guess that is because on this cruise it was warm enough to go outside, so many did. We don't drink. The drink people come by a lot, but we just politely shake our head no, and they quickly move on. It didn't bother us at all. We bought a soda card, 12 days of all-you-want for $50. Not bad.
Our cabin was always clean. Steward was friendly, and we never ran into him in our cabin. He seemed to watch carefully for when you left, then swooped in to get it cleaned up before you came back.
Ports were great. My experience is that Princess almost always docks early, and leaves the port pretty much right on time. It seems like they will wait about one hour if someone isn't back on board yet. (you can tell, because they start calling for them, just in case they made it on board with out checking in (but also to politely publicly shame them into being on time next port :)))
We don't use the expensive stuff like the spa, so no comment there. We had a window cabin, and walked down one deck and sat on deck 7 outside every night in a deck chair. We joked that it was our balcony, we just had to share it with a few passers-by.
Overall, if you remember this is a ~$200/night cruise, and not a $600/night cruise (crystal, yachts of S, etc), I think it is nearly impossible to beat!