Line cutters are ideal for technical diving or cave diving where the main entanglement risk is from guideline or fishing line. They're small, low profile, and stay sharp as they don't get used as pry-bars, screwdrivers, and bottle openers. They can attach to your computer or BC webbing for easy storage.
We recommend having one on every computer wrist strap, so you're never caught with your hands entangled and a knife out of reach on your waist.
If you are underwater gathering, a combination of divers knife and line cutter is ideal. One for hunting, one for emergencies.