Me, NONE of them.
Look at the negative feed back at newegg. 29%, 36% (OUCH), and 26% respectively.
For EX, the Seagate you listed: http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Compare to 13% and 15% for the two options listed below.
Currently these are the only two drives I buy. WD has some more expensive and reliable drives, such as the RE series, But ofCoarse, COST MORE.
I'm doing HDD research right now too. I also am looking into RAID controller cards (e.g. Areca, Adaptec, LSI, etc.). Interesting thing: read the HDD compatibility sheets from some of these vendors, and they shed some light on overall vendor quality in terms of standards adherence, DOAs, and longevity. For my next set of drives, I'm going with the WDC WD2003FYYS (RE4 2 TB, not green), since they'll be in RAID arrays. If you're going AHCI / JBOD, the Cav Blacks are good indeed.
I ran into problems with the Hitachis on a 3rd-party controller.