We have travelled with P&O a few times and always still have a good time. Below is a list of things good and not so good.
Good:
a) "Salt" by Luke Managan. This is a great speciality restaurant and worth the high cover charge of $49 pp for dinner or $39 for lunch. We celebrated out anniversary and the service and food is amazing. The steak was great - especially when it is the only steak on offer on the cruise ship.
The cabin was very roomy and comfortable. Beds need attention. Even though okay to sleep on, had a few lumps in the mattresses.