We booked this fairly lateish about 5 weeks before sailing. I was looking at Celebrity for an itinerary that took in Dubrovnik and Venice and this hit the spot and was a happy coincidence that it was the same ship as our 11 niter out of Rome last year to Istanbul / Athens.
Barcelona cruise terminal seemed so much better organised than Rome and we were checked through and on the boat in under 10mins (incl walking time).
The boat was again lovely although i did notice a couple of minor gripes with things not been spick and span on board. Again not bad enough to mention to anyone but all the same slightly disappointing.