That really depends on your definition of "better". I like amano shrimp myself, both the regular and the cherry reds.
They also perform different tasks and have slightly different care.
What are the basic differences (care + tasks)? Am toying with the idea of either, would help if there was a deciding factor.
Ghost shrimp are scavengers, basically throw them in your tank and forget about them.
Amano shrimp are less scavengers but still are scavengers, shrimp are scavengers which makes them a bit dirty, tasty but not always good eatin. Amano shrimp can eat algae, especially hair algae. Amano or a lot more expensive usually but aren't considered food for other fish. If there is little algae in your tank and leftover food you can add a part of a algae wafer to substitute food.
Really your decision will depend on what you want done, if you want a shrimp for scavengers I would go with ghost shrimp or mostly ghost shrimp, if you want a shrimp that would eat algae you would want amano shrimp.