I have a silverstone ml03 case and I use 2 enermax silence fans. http://www.newegg.com/Product/Product.aspx?Item=35-214-016 They run full speed at 1600rpm and I'm pretty happy with the noise level and airflow. As wiley165 said, what environment is the pc in? Closed cabinet, shelf, or out in the open. I've been testing mine and 2 fans seem to be fine along with some cooling in my cabinet.
3/6/14 at 3:18pm