I really wish the Banana Pi BPI-R3 mini came with a USB3 port and two A7x cores in addition to that quad A53
it's an interesting little device though! I just wouldn't use it for any sort of USB NAS ... it's really gonna be best as a router (especially with 4G support!) and not much else, but it could act as a light-duty data sink in a role like keeping a Syncthing hot copy of your personal documents if you put a tiny NVMe stick in it though.
that Mediatek SoC should have good #OpenWrt support - keyword *should* - don't trust Me (I haven't checked), do your due diligence before buying one!
https://www.banana-pi.org/en/bananapi-router/149.html #DIY #SBC @bananapi