Synology. Their software is the OS X of NAS's. Everything is laid out logically and they have great long-term support. They're the only NAS manufacturer with a statement about Meltdown that I could find.

Try it here if you want: https://www.synology.com/en-us/dsm/live_demo

Build your own and use one of FreeNAS, Rockstor, or roll your own (as I have with ZFS on Linux).

I can't recommend any competitors specifically since I've just been building my own, but last I looked drobo didn't look that bad.

Synology is arguably the best you can buy. Their long-term support is great, and the bundled apps are great by first-party standards. Their Knowledge Base covers every detail you would need to harden your NAS setup, including HTTPS w/ Lets Encrypt.

I really love my QNAP device, but the software stack is so amazingly complex it sort of scares me how many vulnerabilities might be lurking. Hopefully the QNAP security team is full of decent folks.

For reference, I have a QNAP j3455 device. Remotely streams up to 4 hardware accelerated plex streams, runs lots of SSL connections, hosts all my files in a myriad of cool ways, never gets about 30% CPU load. It's amazing.

I build my own with Unraid.

https://lime-technology.com

I was rather hoping that someone would list some low power options. When I look into building my own, I usually end up looking at what is basically a PC, with typical PC power draw.

Build your own and use freenas or unraid and firewall it off..

I use a 45drives 30 bay storinator and the thing is a tank.