My players and I loved this one shot. I stumbled upon it one day when I was looking for one shots I could keep in my back pocket. When half of my game group needed a one shot adventure to play when the rest of the group couldn't make it, I busted out the Boneyard. It was a big hit.
It's well written, easy to run as is, or customize. Also easy to scale. Took us 3-4 hours to play with three 3rd level adventurers (whipped up that night). A little bit of spookiness, a little bit of mystery, and a lot of fighting undead.
Only one player went down in the final showdown. Although, his life was saved by the Cleric.
[5 of 5 Stars!]