Pros: Large amount of storage space and easy initial setup.

Cons: Slow transfer rates, MAC permission issues, No backup Disks or images of OS

Overall Review: When I initial brought this it was to provide ample storage for my ever growing digital collection of pictures, music and videos. Initial intention was to house my 1.5 TB of videos and accessfor streaming. The transfer rate was horrible. Even for moving pictures for back-up storage. I know that transfer rates depend on slowest connection in the topography, but when you have everything connected to a gigbyte connections and nothing else running on the network, moving or access files and folders took extremely amount time. I compare it to when I use to use dail 9600 Baud rates. My second CON, was that my computer is an iMAC, always running the latest and update software constantly had permissions issues. When the accessing folder in the Public portion of the drive, a person had to ensure that they were accessing with the guest login, so none OSX computers could acces the files correctly. If you logged in with a created account that had admin rights, you wre still denied access. After extensive research in the help section online, did I discover that there were known issues permission and MACS. My thrid CON is dealing with upgrading or replacing the hard drive disks. Since I was having such slow transfer rates, I decided to swap out the (2) 3 TB drives with (2) 2TB so I could take better advantage of the larger drives in my iMAC. I followed all the documentation provided for replacing or swapping out the drives. Once I had the 3 TB drives out, I formated for use in an iMAC and installed. Perfect installation. Then I went to setup the 2 TB drives and that is when my problem began. I hooked back up the NAS and nothing but an orange light. After checking support documentation online, I discovered that the OS image is located on Drive "A" of the dual NAS and the only way to get a copy of the image (partition) is to copy directly from the drive or another similiar NAS drive. My delimena, no image or noone with a Dou Live system. Now my NAS is a brick. There is a bunch of work arounds in the Western Digital Community Support pages, but all require a working knowledge of working, scripting in a linux terminal that seems to have a hit or miss percentage. Western Digital should provide better documentation and warning on swapping drives and provide a disc with atleast a restore image. What happens if you aren't setup in raid and utilizing disk spanning as I did, and the drive with the os fails and you can't recover it? So with that, I would be cautious with buying this product or any of the Dou Live Line as I am sure all are setup and designed the same.