It's quite hard to pinpoint which case fans are "the best". Testing and reviews are relative to the reviewers and their individual test setups. There are a few brands (like Corsair, Noctua, Thermaltake, Fractal Design, etc) that are more popular, but none of these brands have been proven to be a clear #1. The best thing for you to do is filter your selection of fans by the features you want (like LED's) and then choose a fan that has good reviews.
It's quite hard to pinpoint which case fans are "the best". Testing and reviews are relative to the reviewers and their individual test setups. There are a few brands (like Corsair, Noctua, Thermaltake, Fractal Design, etc) that are more popular, but none of these brands have been proven to be a clear #1. The best thing for you to do is filter your selection of fans by the features you want (like LED's) and then choose a fan that has good reviews.