I think it's fabulous and riveting so far. much has happened in 50 pages: surprises; reasons to worry about at least one of the characters who, so far, is still alive; furtive, late-night shenanigans; an amateur sleuth at odds with the manner and technique of a police inspector who wants to monopolize the case; lots of Scottish accoutrements, which I love; a well-loved and respected victim, which plays against a perhaps more familiar scenario where the dead person is loathed by many suspects (but there's something there...something about her strict religious views, more discipline, less forgiveness); not many people at the castle when the murder must have occurred; and my memories have previous Mysteries have had me swap out Ngaio Marsh's Off With His Head, for that other one, Scales of Justice (it's the scale angle).
besides that, our amateur sleuth here, and some of the feel of the case he will slyly be working on (copper would rather he didn't), reminds me a bit of the Mordecai Tremaine books by Francis Duncan; the author lets us know when the sleuth notices a change in a character's manner, or gives a hint that something may be important because we know that the detective has noticed it. we are left trying to figure out what the detective has got wind of, maybe merely from a few words uttered, or a change of attitude during one question put.
so far, this is a book I am anxious to return to, and am ready to lap up. I am very happy with it!