The p182 will be much quieter because thats the design aim and it looks very nice. See those vents along the side, they do that so that there isn't a straight line between the noisy bits and the outside of the case. It also has rubber isolation for the drives so you might not even realize its on.
Simple evaluation - p182 = refined/quiet, 900 = airflow/overclocking/enthusiest. Its two different market segments.
Tease.







