Hi there we have been on most of the P&O ships, as well as having to been to many ports around the med, and in order to give you useful advice would really like to know, what time of the year you are planning, which ports of call and most importantly which ship.
Also, have you cruised before? What are you hoping to get from this cruise/experience, and how many days are you thinking of.
For someone in their 20's I would strongly suggest you also take a look at Princess Cruises, either sailing still from Southampton, or as a fly cruise getting you to the action of the Med without the 3 days there & back.
But of course that is something only you can decide.
We are a 'few' years older and love all the activities on Princess, whereas we can struggle to find a full evening's entertainment on P&O.
So if you can get back with some more info, we'll do our best to give you our thoughts.
Alan & Katrina
Last Cruise: Queen Victoria January 2016
Next: Nothing booked