The Witches of Hagswallow from Sleeping Griffons Productions. this OSR adventure for 3-6 PCs of 2nd-4th level comes in at 45 pages (45.2 MB) for $2.99 over at DriveThruRPG.
Right off the bat this PDF is unsecured and while technically bookmarked, the four bookmarks don't take you beyond page 5. Outside of the cover and a few markings on the pre-gens pages, this PDF is a black & white affair, which makes me think that 45 MB is just way too big and was not optimized at all. I'm fairly certain that while the pages appear black & white, they are full color instead.
My initial, quick flip-through brought to my attention a couple of things. 1st was that the writer doesn't like to re-use monsters and prefers to place full monster stat blocks in the adventure body instead of a dedicated bestiary section*. There are actually some monsters re-used, just not heavily like I've seen in far too many adventures. Some folks prefer a bestiary and others loath them. My preference is a bestiary, but to also include a smaller in-line stat blocks where the monsters appear in the adventure itself. I think these are more a matter of preference and what I focus on is usability when running the adventure. I also noted that this adventure has plenty of small bits of accent art that isn't required, but used to fill-in at the end of sections to help with pagination.
The adventure was a relatively easy read and I appreciated the editing that clearly took place as the information for each section felt well-suited for the task at hand. I do wish that there were some marked flavor-text boxes because some of the entries felt like they were starting out with flavor text (or close enough) but there were often bits of detail you wouldn't want to share outright. As a GM I think you'll want to go through and highlight flavor text-worthy bits and denote some of the room's special details. Nothing really out of the ordinary there though....
Two things really stuck out for me from my read-through. The 1st was that I liked the presence of a story-within-a-story that the players might not ever even hit upon, but the GM could use as a broader arc. There was also a fundamental change to a monster that I just didn't agree with. I won't dive into that detail because it is an easy-enough crossed out line on my working copy.
The Witches of Hagswallow and It somehow felt "right' to me. Easy enough to ramp up the difficulty or pull it back some and I saw some nice touches that I think lend themselves to some good role-play. The inclusion of full-page pregens was a nice touch (and a good selection to boot). This adventure seemed like a good one to have in your "back pocket" to run as a one-off if needed, or to slip in to your own campaign/game world. Some of the behind the scenes big-picture stuff is enough for a GM to play off of on their own, or you could wait for some follow-on adventures to come out. Either way I think you get a good run for your $3.
*When I started to actually read the adventure I realized I had somehow flipped past the bestiary and right onto the maps.