Useful start to take a quick look at the system. Has enough crunch to explain the basic mechanics in full, and enough content to whip up a party of starting-level Dwarves - the full set of starting rules for each Combat Role, and brief descriptions It doesn't have any information for character advancement (which in the bigger books is revealed to be an upgrade system, each Skill and Role having its own specific set, purchased with points earned by doing missions for the clan rather than defeating monsters per se, which is cool) and only some brief worldbuilding, but does contain a useful selection of monsters and a couple of the generators for making mountain paths - which is surprisingly handy for getting a sense of how stuff in the bigger books work, even as the pre-made mission didn't strictly need them.
Possibly the most significant bit of character generation/setting generation it misses which stands out the most compared to the full rulebook is the Clan generator - obviously intentional, as the basic game has you arrive at a specific clan after the mission is over, so I presume the intent is you can play through this thing, get a sense of if you like it (Which hopefully you do; it's good!) and then head off to buy the full game and then have the very next session be generating your own groups clan and getting into the game proper. Not a bad way to set things up, I guess; just notable to realize the Clan is intended to be a major part of the campaign going forward later. Not that you couldn't just stat up the one hinted at in the Quickstart guide, of course, if you were so determined!
Not much in the way of artwork, but what is there is representative of what the rest of the rulebooks contain - black and white linework characters, with everything else being otherwise merely tidily presented. It's enough to get a passing mark, if not bonus points in the content stakes.
And hey, it's (potentially) free. It's hard to knock a solid system releasing the basic rules like this, and the production quality is representative of the rest of the line.
PROTIP: If you're buying just the one rulebook for the group, you really want Axes And Anvils: Under The Mountain, because it has the entirety of all the players handbook in it as well as the setting information, rules customization benchmarks, elves & humans as PCs, and even more generator goodness.
[5 of 5 Stars!]