ONE big issue with any ext. HD, that these are NOT permanent storage devices. They also shouldn't be used a the sole source of data. Don't dependent on these as the media to store important data for long. Check this forum or google away the results or requests of users trying to recover their data. Protect data, have multiple sources of back-ups.
Next, you're not going to find that many brands of ext. HDs out there. there maybe various models or levels of storage available but overall only a few makers. Take my advice handle these as if they were eggs. They do fail due to improper dismounts, handling and ESD(static) damage. So, with that in mind, don't get comfortable and then find a day were your data is stored on ext. HD and can't recover due to some hassle.
As for a brand, decide on storage amount, for me select a Seagate and "small" size using 2.5in HD. These tend to require less power to run BUT!!! if needed can use an ext. power source. Understand, some that use power from PC can cripple a USB port as it is a demanding power user. So, I like ext. AC powered HD. Last, one trick that should be used is the use of Velcro or non-slip mat where the ext. HD rests on desk or work area, so it don't fall victim to "droppage".
IMHO, I like Seagate ext. HDs, take that as you will.
I am looking for an external hard drive to back up my present laptop and desktop computers. I don't want something that is going to be obsolete quickly. I am thinking a 1 or 2 TB hard drive. I will be purchasing probably a new all in one for my main computer, I saw a 23" Samsung w/ Windows 8 that I really like, and a new less expensive desktop for my home office. I may look into another laptop in a year or so. What brands should I look for? I am looking at a Western Digital 2TB My Book Essential right now. This is just under $100 at this time. What features do I need to be concerned about? I don't have a ton of data to store but that could change. I just want to get the best unit for my money.
Any info would be greatly appreciated.