If you won't want to spend around $400 on an Oculus Rift or $500 on an HTC Vive, Windows Mixed Reality headsets are a great value. They work with SteamVR, they don't require external sensors, and they even have higher-resolution screens than the Vive and Rift. Right now, you can get Lenovo's Mixed Reality headset for $199 from Microsoft's eBay store—$200 lower than the original price.
The Lenovo Explorer has two 90Hz 1440 x 1440 LCD screens (one for each eye), with a 105-degree FOV. Like all Mixed Reality headsets, it uses inside-out tracking, so you don't need to set up senors around your room. There is no built-in audio, but a headphone jack is mounted to the headset, so you can plug in your own headphones/headsets. Two motion controllers are included.
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