In terms of tactics and sheer power, Nanoha has the advantage. (For crying out loud, the lass is a flying tank.)
In range of skills, flexibility and unpredictability, Sakura has the advantage. (She just needs to use the Time Card then stab Nanoha using the Sword Card. But if she wants to be cruel, She'll use Illusion Card and Loop Card to put Nanoha in an endless maze.)
