I loved this - Kristen’s performance is astonishingly good but it is a strong film in its own right. It is really a horror and brought a few echoes of The Shining - the long shots through the set, the minimal dialogue and the sense of a descent into something (despair in this instance, rather than madness).
I can’t agree with the comments about the lack of accuracy - it’s not a biopic (and anybody looking for one is going to be disappointed) and nor does it claim to even be a true account of events, so the lack of faithfulness to the outfits of Christmas 1991 or whether the UK did or did not have drive-through takeaway at that point in time seems unimportant. The Naomi Watts film reached for physical and historical accuracy and didn’t end up even vaguely achieving either.
That being said it isn’t flawless - William and Harry do require a degree of suspension of disbelief and there was the odd unfortunate continuity error - the ever changing registration number plate on the Porsche for a start!