Haven't tried the AF120's.
Good 120mm fans I've used are
Enermax TB's and Clusters http://www.enermax.co.uk/products/fans.html
Just trying some Aerocool Sharks atm, push a lot of air around and pretty quiet. http://www.aerocool.us/accessory/shark_b12.html
Noctua make great fans but I don't use them as they look like poop.
Depends how much airflow you need also, high airflow, bit louder, or do you need deadly silence?