Had you asked this question 5-6 years ago, I would have said Western Digital without blinking ... but a lot has changed in the past 5 years in HDD technology, and with Seagate/Maxtor merging, I personally think seagate makes a better drive than WD does now .... they seem to far outlast the rest -- however that is for INTERNAL bare drives...
As far as an external drive goes, I have lots of experience with many different drives, and the only ones that are still around that stood the test of time, are my
HITACHI X Series drives ...
I would gladly recommend this drive to anybody .... I have 3 of them that are awesome, and I have bought at least 20 of them for clients, and never heard any negative feeback!
http://www.newegg.com/Product/Produc...-323-_-Product