We decided last year to get married on a cruise. We had previously cruised with Royal Caribbean but they only offered symbolic marriages, so we tried P&O and it seemed reasonably priced (around £1200 + extras). We decided on Oceana as it was a mid-sized ship and the itinerary was good as we had always fancied visiting Rome and Barcelona.
Embarkation was easy, when we got to Southampton we had our car taken within half an hour and our party checked in immediately as we had priority due to getting married. Straight on to the ship and to our cabins - really quick and straight forward.
A little disappointed with our cabin, balcony was very small and furniture not in great nick, also our bathroom was very small. Generally the cabin was clean and decor was fine. As we were getting married, there was a free bottle of wine in the fridge and we had complimentary fresh fruit and canapes every couple of days. We were also given a couple of robes and slippers too :)
Smallish room, small bathroom and balcony. Quiet location, not too much movement.