Hi:
We are going on the QE 2 (P 2 category) on the July 30th Cruise after having sailed in a Princess Grill Suite on the March 9th QM 2 Carribean Cruise. We will let you know the difference when we return. I have a feeling comparing the two is like apples and oranges. From what we've heard the food and service in the P 2 catgory is superb.
Of course, there is no balcony or state of the art fitness center, but this will be more of a sightseeing cruise.
We were first on the QE 2 on our honeymoon in 1972, but then again everything was perfect at the time.