Best Massive Raid option for Plex?

[takagari]

Looking to upgrade my current 12TB storage setup
To a dedicated server setup, Case I have will hold 16HDD's
But whats the best/most stable/expandable option?

I'd like to see redundant raid setup, with expansion options to drop more hdd's and expand the raid.

I see a low of options, but would love your input.
Also like to see something a plex server could be ran on as well

Thanks