Summary: I had one of these drives. The thing started clicking within about a month of ownership. The clicking got and more more frequent and pronounced. Then one day it just wouldn't let me access my folders anymore. Not UNTIL it commenced to 'click' again (if you waited it may start. Then again it might not). Then it would act like normal for awhile. Finally it wouldn't even allow the Desk-Top to mount it anymore. It is now used as a paper weight.
Summary: I purchased this Seagate expansion drive, mine is 500gb. I used it about ten times, backing up various important files. Like my mother's photographs. The eleventh time I plugged it in, it clicked and whined, the hard drive inside crapped out, totally failed and I lost everything. Buy an external enclosure and a good hard drive like Western Digital instead. I have that combination and it's worked hard for more than a year now.
If you treasure your data & $$$ Don't Dare buy this or any Seagate
13 July 2013
Summary: This is the 2nd Seagate purchase where after a year or two starts hearing a clicking sound, loss data and never recover them. It was a nightmare and so I had the hard lessons learned, viewed a few Seagate "how to fix" and it is basically opening the box. After reading all the online advice and contact with Seagate - better try a cloud subscription (i.e. Pictures on Shutterfly or Flikr) or DVD. Hopefully technology gets better.
Summary: I have no technical problems with the Ext. HDD itself but the only thing that really sucks about the this is that when you plug it in, it will ask if you want to install some software. Of course it's optional, but for someone who is using it for the first time... I suggest not to install the software, it will give you a trial and after the trial expires it will pop up annoying boxes telling you to renew.