Hardware Choice Pi or PC?

Whew, a OH box does not have to perform I/O like a fileserver has to. You don’t need to care about USB3, SATA or TRIM.
A RPi2 or 3 is fine. If you really wanna go with an Odroid, better check out the C2. More bang for the buck, you can even run a 4K capable media server in addition to OH if you want to.
And as - surprise - you’re not the first to raise this topic, check out this thread for an older discussion. Also check out the link at the end of this thread for a comparison of single-board computers.

On SD (and even SSD!) corruption, check out this post.