I appreciate most people at this point in the iphone 8's lifecycle (and I assume the X) will only get official Apple repairs. But be aware that if you replace the screen at a non-authorised dealer then Apple will brick your phone at the next OS upgrade.
https://www.youtube.com/watch?v=FeUBdMU2qA0&t=330s
https://www.youtube.com/watch?v=FeUBdMU2qA0&t=330s