Need a NAS or DAS

[ed]

Yes, NAS is easier to expand and upgrade. I would rather look at Qnap TS-464 or TVS-473A (with GPU card upgrade).
These support 10gbe upgrades and have multimedia support.
DAS boxes that are faster then 5Gbit/s are Thunderbolt based models from Pegasus, Areca etc.

I hope this helps.