Bests & Worsts Reviews from Amazon

I bought this because I wanted to back up my Mac before I updated from Mavericks to Yosemite. I created a Time Machine backup using this, and all seemed well. When I updated to Yosemite I found it too slow and hard to use, so I decided to restore my Mavericks backup that was stored on this drive. I did that. When I opened iPhoto, I was unable to view many of my photos! There was an error because the original photo files could not be found. I thought "no problem" and looked through the backup of my Mac, hoping to find the original files. But I found that they they were never backed up and/or corrupted! I lost hundreds of photos and videos as a result. I made a terrible mistake placing my trust in this product.