[hdmkv]

looun is right... if you don't need 3D, I'd pick Chromebox first, followed by nVidia Shield TV, followed by WeTek Core 4K (based on wrxtasy's review), followed by RPi2 .

You might need to add the Shield on later date

If nVidia adds MVC h/w decoding (lots of requests for it here; please add your voice if you haven't already), man, it'd be the ultimate all-in-one home theater box.