FWIW - The equivalent WD drives are cheaper and in the lat year or so the cool & quiet equation has flip-flopped now that WD is also using fluid dynamic bearings. The WD drives have gotten substantially quieter and the Seagate ones have gotten rather louder. The Seagate drives still have a longer warranty, but if you end up needing it, your data ia probably gone anyway...
OBTW - MicroCenter charges ~$210 for the 500Gb SATA WD drive but has an $80 rebate offer going until Dec 31st. This beats the best price on these I found using PriceGrabber...