There was a constant problem with the hard drive maintaining its partition formatting so that it could no longer be read, and no longer function as the backup drive I needed it for. I reformatted the drive following the advice of Seagate chat support, but no matter what I tried, the drive would work for a short period (one to seven days) then would become unreadable, necessitating an erase, a reformat, and over 10 hours of backup time. Over and over.
Finally Seagate replaced the unit with a refurbished unit, and this transaction cost me ten bucks for shipping back the old unit. But, in the end, the new unit acted exactly the same way, with one difference: it became unreadable almost immediately after reformatting.
Despite the problem seeming to be on Seagate's end, they would not refund my shipping costs.
Luckily, Amazon's great customer service came through and allowed me to return the unit for a refund, and Amazon paid the return shipping! I'm buying a replacement drive (this time a Lacie) from Amazon.
Another shortcoming of Seagate Backup Plus is that it comes only with USB 3.0 connection. Other connection units are available, but at a ridiculous price. It cost me $80 for the Seagate adaptor that allowed me to connect with Firewire 800, for a part that is worth maybe $8. And, in the end, I was not able to get a refund for the adaptor from the Amazon seller SHOP ZONE, so I also don't recommend them.
Amazon: wonderful service. SHOP ZONE: not so much. Seagate: bad experience.