We were on the New Years sailing of the Costa Atlantica (PS 6219) and have also been on Celebrity, RCCL and Norwegian. In my opinion there was not a lot of difference between the quality of each of the cruises. We thought Costa was definitely the best value however- the price was very good for quality comparable to the more expensive offerings of Celebrity and RCCL. I would also say the food was comparable across all the lines. In my opinion NO mass market cruise line offers true 5 star dining - it is more like good or very good banquet food (except for some of the optional restaurants). Given this, we quite enjoyed the meals on Costa and many items were VERY good. The buffet also was quite good. The only thing that needed some improvement was the breakfast buffet as it was EXACTLY the same every day. Certainly I would not say that Celebrity was any better in the food department (in my experience). Some differences between the lines are the greater proprtion of non-English speaking guests on Costa but we had absolutely no problem with this. I had worried about smoking but never found this to be a problem at all. Also I felt that the Costa ship was the most uncrowded of the ships I have been on - even though it was at full capacity of 2700 we could always find lounge chairs on any deck- this was not my experience with RCCL or to a lesser extent with Celebrity and NCL. Given the great value I would definitely sail Costa again.