Take a look at the menus for both and go from there.
I *really* wanted to do Coral Reef because my kids love all that underwater/sea world stuff. But, after looking at the menu, there's just no way that we'd come close to being "satisfied" with our meals and I could totally see us all walking away hungry. We just aren't seafood people.
I opted to cut Coral Reef and keep 50s Prime Time. The menu is more appealing for us, the prices are better, and I just think that my kids would enjoy the combination of food and atmosphere better. At CR, my kids would've loved the atmosphere but hate the food.
Just some things to consider.