I've played RPGs before, but had never been DM until last week. Beyond the Wall gave me the perfect starting point and framework to build plots and stories around, and the playbooks were helpful for players who were completely new to RPGs. The simplified rules (compared to traditional D&D of various editions and Pathfinder) I found massively helpful, while still containing elements that I found familiar and was expecting, like ability scores, alignment, etc.
The premise of all the PCs knowing each other and all living in the same village was helpful too, and makes the world seem more real, while giving plenty of opportunities for plot hooks and motivations.
I really liked this, and after purchase I downloaded the other free materials that contain plenty of ideas for future adventures, how to build encounters, monsters, villains, and the like.
There are a few elements here and there that aren't explained perfectly from a new DMs point of view (I had to read through how hit dice worked a couple of times) or don't seem to quite work (breath weapon saving throw to dodge things that aren't breath weapons) but there are alternative rules and workarounds, or you can just adapt these as you see fit.
Overall this massively helped me to springboard back into RPGs after a break, and was a lot more accessible than many other systems I've seen.
[4 of 5 Stars!]