I have sailed on both of them.
I did not see any negatives. I had a wonderful cruise both of those times. There is a lot to do, there was great entertaiment, the service was quite good.
The boarding process was very smooth and you don't feel crowded on those ships because there are many places for a person to go and have fun. I did the Zip Line and saw all the shows, made new friends and would recommend those ships to any fun-loving person.
Carnival Liberty New Year's Eve 2007
Liberty of the Seas 5/2008+11/2009
Allure 1/16/ 2011
Vision OTS 2-14-2015
Freedom OTS 3/6/16