Apple's Face ID on the iPhone X works just as well as Touch ID, and that is excellent indeed for a first generation technology. Having used the iPhone X for a month now, Face ID has integrated nicely to the workflow, and its infrequent hiccups are no more annoying than those of Touch ID.
When it works, Face ID is imperceptibly fast; the mechanics of it disappears into the background. Looking at the phone as I swipe up from the bottom in one combo motion, and it unlocks like magic. The only time I even notice Face ID is at work is when it inevitably doesn't work: having the phone buzz at you and prompting a passcode entry is as baffling an experience as Touch ID rejecting my thumb because it's slightly damp.
Thankfully, those moments occurring are miniscule, and half the time it's my fault (if alive, Steve Jobs would say I'm using it wrong). To the surprise of nobody, Face ID doesn't work when my face is half covered by a pillow or wearing a face mask. Sometimes even too sudden of a change in hairstyle - if I were to flip my hair up from its usual down position - would trigger a recognition failure. I hope hats don't interfere, because I've yet to use Face ID while wearing one.
As I've said in my initial impressions, I think Face ID needs an additional biometric layer to complement the base systems: a retinal scanner can alleviate times when the face is covered with a mask, or I happen to be scratching my nose. Being able to still securely unlock the iPhone with an impeded face would be the ultimate.
What Apple has engineered with Face ID is phenomenal: it's an exponentially better and more complete user experience right out the gate than Touch ID's initial debut. With further software development and deeper machine learning, I hope the technology gets better and migrates to other Apple products. It would be lovely on an iMac.