I don't think you need to worry. Sure, some things ain't what they used to be and yet P&O are probably carrying around more people than ever before so it can't be too bad. If, at the end of your cruise you didn't enjoy it then be prepared to put it down to experience and take away the positives. Like anything in life if you go in with a positive mental attitude then the chances are that you'll come away wanting to book again - I hope so. Promise me one thing, that when you get back you let us know how you got on!