I'd get the one with the 32MB cache and the 5 years limited Parts and Labor Warranty
Seagate Barracuda 7200.11 ST3500320AS 500GB 7200 RPM 32MB Cache SATA 3.0Gb/s Hard Drive - $69.99
http://www.newegg.com/Product/Produc...82E16822148288
(Free "UPS Guaranteed 3 Day Service" shipping too).