I currently have a Seagate USB 3.0 external drive, and it has been great. I don't use the software bundled with the drive: I simply use Windows 7 backup.
This Seagate drive is actually a 2.5 inch laptop drive, and is powered through the USB port. If you want higher capacity 3.5 drive, you'll have to get one that is self-powered.
I recently bought one of these on sale: ORICO 6518SUS3-BK USB3.0&E-SATA SATA HDD Docking Station/Enclosure. Buy any bare SATA drive (retail or OEM) and insert it into the dock. It works with both 3.5 drives and 2.5 drives.
The dock supports USB 2.0, USB 3.0, and eSATA. If you are going to go with a self-powered drive, I suggest eSATA: it's faster than USB 3.0 for random access. For sustained read/write, they appear to be about the same.
Thanks. I;m looking at the Amazon comments and there’s something about Seagate that there is a back-up problem if done auto but manually, it’s the best.
Just by reading the AMZ comments..