The free quickstarts that many systems have are an incredibly valuable resource, both for promoting and learning their game. Whether they're just an adventure with pregens and a rules summary or a full little rulebook in and of themselves, the ability to pick up and try a system at no cost, and without having to peruse a whole book, is fantastic for getting both players and gamemasters into it. With all that said, what do you think are some particular hits or flops among quickstarts, and why?
Personally, I think the Call of Cthulhu 7th one is one of my favorites, somehow containing everything players and even keepers realistically need most of the time while still being conveniently small and nice looking. On the other hand, I'm not a huge fan of the 13th Age 1e quickstart (though I am a huge fan of 13th Age), which while fine for people already familiar with F20 games, explains very little except for how it's different from those, and doesn't include pregens or adventures in its own page count, all together which make it much less useful for introducing newcomers to the game, in my opinion.