I've been using this DS218j for about a week now and it meets my needs very well. I just needed a place to store photos, music, and videos on my network, and a place to back up shared data files. I also wanted something to control a couple of security cameras. For media servers and surveillance applications, memory usage is around 45% and CPU usage is low, averaging around 10%. I have a couple of 2T drives configured as RAID1 (changed to RAID1 with standard SHR for better performance and simplicity). An SFTP server is also set up because I use it occasionally. If all you want is file sharing to your network for media and backup, control of multiple cameras, and the ability to have your own cloud storage for portable devices, this is perfect. If you want to transcode or access it from a large number of users on your network and/or do a large amount of file encryption etc. you can upgrade to a higher tier with more memory and CPU power. Update 08/21/2019: I still love this NAS. Since the initial setup, I've installed the Synology Media Server app and it has worked flawlessly to stream music and videos to my smart TVs and tablets. I also set up port forwarding for the surveillance station and checked my security cameras using the DS CAM app on my phone. I have no negative complaints about this NAS. It worked flawlessly for me with the apps I used.
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