We took a look at the Archon in April this year and it recieved a lot of praise. Now reciving a new, larger 150mm fan, it would be interesting to see how this revision affects performance. Generally speaking, a larger fan needs to spin less to produce similar airflow to a smaller fan at a higher RPM thus larger fans are quieter. The new bundled fan is rated by thermalright to spin at 500-1100RPM with sound pressure at 19-23 dBA.
Product page: http://www.thermalright.com/products/?act=data&id=184&cat_id=27