The YouTube channel Tested went to Valve recently to play a few hours of an early build of Half-Life: Alyx on a variety of different VR setups, from Valve Index to Windows Mixed Reality and the original HTC Vive and Oculus Rift. Though they're focused on the headsets rather than the game—which is clearly still in a very early state—they do seem quite impressed by it.
As Tested cofounder Will Smith (not that Will Smith) says, "The amount and quality of art in this game is outstanding. You can interact with so much stuff, you can force-pull it over to you. The verbs that are accessible to you as a player are amazing, and the sound is spectacular. There's dynamic sound all around you, You can hear things above and below you and the levels are vertical and expansive. I've been thrilled so far."
As well as testing Half-Life: Alyx with a variety of headsets and controllers they tried both teleporting-to-move and push-to-move, as well as playing it standing and seated, and seem impressed by every possible configuration.
The short amount of game footage shown mostly involves explosive barrels being used against barnacles, objects being hurled with gravity gloves, zombies getting shot, and headcrabs being manhandles. Someone has stitched together all the gameplay footage if that's all you're here for, though be warned they've soundtracked it with monologues from Half-Life 2 and the music from Boneworks which is a bit distracting.