We travelled on the taster cruise to Guernsey, with friends celebrating a birthday. Thanks to them we had a terrific time, but if we had been on a more normal cruise we would have been much less happy.
As others have said, things did not get off to a good start with painfully slow boarding. On the ship though, we liked the decor and the facilities and the food was universally good and to our liking. We did not join any of the onboard activities but did enjoy some of the entrainment - especially Paul Zerdin, who was hilarious. The less said about the Abba tribute band, the better!
On the less happy side of things was the service. In the Concerto restaurant at main meal times service was excellent and everything we could have wished. At tea time in the same restaurant it was rather chaotic, but still friendly. Around the atrium area and in the bars, though, service was dire. Too many staff had a poor command not just of English but also of their jobs - asking for peanuts at one bar proved to be a rather unpleasant experience, with a response bordering on rude. Service in the coffee bar in the atrium was very slow indeed.
In the stateroom, we liked the decor and fittings but, as others have said, we wondered what the designers were thinking when they placed the toilet roll holder and the few plugs. The balcony of what was supposed to be a premium cabin was also very small.
In time, Princess might actually get around to training staff adequately and that would improve the experience a lot. I would not want to go on a long trip with the staterooms the size they are, and I fear that the ship when fully loaded would be very crowded - it seemed busy even with what was rumoured to be only half the potential number of customers.