Stephen_144 :
Why would I consider a VR headset, such as the Rift, as a competing purchase for a Windows MR headset like the one above? Both do what the other can not.
The current Windows MR headsets, including Acer and Samsung, are VR headsets, not AR like the Hololens. The MR (Mixed Reality) here refers to the Windows API they support, which handles both VR and AR, even though each headset is only one or the other. (And most of them are only VR.)
The main difference between this Acer and the Rift is the WMR headsets use "inside-out" tracking while the Rift requires several wall-mounted base stations to track. The result is mostly the same, but the Rift requires more physical setup. The Rift might have better tracking in a few edge cases, but WMR has easier setup.