I have a XU4, I use it as a NAS. Get the C2 because it can do H.265 4K/60FPS and H.264 4K/30FPS. XU4 is more powerful, but it is not media ready, C2 is media ready.
Gadget enthusiast
Kodi player on an oDroid N2 4 GB with latest stable CoreElec
Sony Bravia KD-55XF9005