First time on a Princess ship (previous experience has been all Celebrity) - so my faults lie strictly with Princess' policy and not per se the Royal Princess. The easy part first: The RP is very big and we had 3,600 people on the cruise; however, for the most part it seems like only half that many are aboard. The cabins were small (we had a balcony and it was difficult to move around inside - worse on the balcony). The food was good - not great - but good (equal to a 3* restaurant - maybe 4* on some nights). The one pleasant thing was the servers - they were all great and efficient. Shows were OK - again, not great but OK. I really wanted to love this cruise but there were too many things that stood in the way:
1) We missed a port because of high winds - Princess did nothing for the passengers (either monetarily or some type of acknowledgement - other than "sorry".
2) The longer you stay on the ship the more frustrated you get with Princess "nickel and diming" you. You go to one restaurant and order tea and there is no charge - go to another restaurant and they charge $1.59 for the same tea. They charge you for shuttles when other ships would not charge you. They charged for "taxi boats" in Venice whether you planned to get off the ship or not (you had to go to the desk to get a refund.
3) In the fitness center one had to pay to get a bottle of water!
4) Off to see a port - you can buy water from Princess for $2.50
I could go on but the bottom line is that Princess is trying to act like it's a 5* ship but in reality it's a 4* - which isn't bad but if everything were up-front then there would be less criticism.