* Note: Except where noted, all Street Prices were taken from Newegg.com. Three of the HDDs were not available from Newegg: The Samsung EcoGreen F3 2TB Street Price was taken from excaliberpc.com; the Seagate Constellation ES 2TB and WD RE4-GP 2TB Street Prices were taken from provantage.com. All Street Prices are as of April 6, 2010.
There are a few tidbits of information that warrant some additional exploration. First up, is that all but one of these drives uses Ramp Loading technology to park its drive heads. When a drive that uses Ramp Loading powers down, the sliders that hold the read/write heads are moved off of the platters and safely stowed onto a ramp. The one exception to this is the 2TB Seagate Barracuda LP drive, which instead uses the older Contact Start-Stop (CSS) technology, which physically rests the read/write heads on the platters when the drive powers down. Allowing the heads to physically touch the platters can cause additional wear to the platters and presents a number of potential problems, such as stiction, where the head actually gets stuck to the platter. Not to say that the Barracuda LP will necessarily wear faster than any of the other drives or suffer from stiction, but it does bear noting that the Barracuda LP has the lowest rated load/unload cycles of the group at 50,000. All the other drives are rated at least at 300,000 load/unload cycles.
Speaking of load/unload cycles, both the 2TB WD RE4 and the 2TB WD RE4-GP enterprise drives have the highest-rated load/unload cycles at 600,000. As previously mentioned, these two drives--along with the 2TB Seagate Constellation ES enterprise drive--also have the highest-rated MTBF of 1,200,000 hours. It is in part these high-reliability ratings that make these particular drives good choices for use in servers and other enterprise applications. The Constellation ES drive that we looked at is a SATA 3Gb/Sec drive; but it is also available in a SAS 6Gb/Sec version (model number ST32000444SS, street price: $332) that also includes a 128-bit government-grade Self-Encrypting Drive (SED) option.