Machete is one of the finest weapons in the core set. It's cheaper than the .45 Automatic, not limited in the number of uses like that or the .41 Derringer, and it's damage bonus is reliable too. The only issue is the need to be engaged to an enemy - and only one enemy - to get that damage bonus. Even if you can't, though, it's still as good as a Knife, and often you're only having to deal with one enemy at a time.
It's a great weapon for Roland Banks or "Skids" O'Toole, though it's less clear that it's a good choice for Zoey Samaras, as it seems to her advantage to engage with as many enemies as frequently as possible. If used in a group with Scrying to control the flow of encounter cards, it's a really useful weapon for Roland to have; keep him engaged with only 1 enemy, damaging lots and gaining clues.
This one is one of my favourites, because it is middling priced, effective, doesn't use ammo, and in an uncertain world, reliable.