Handsaws are made of steel. Fortunately all steel isn't made the same. Some handsaw feature run of the mill common steel while others are made of high quality Japanese steel. With high quality steel, your cuts will be much cleaner and the blade will last far longer than a standard blade.
There are different style tooth designs that make most major cutting jobs efficient and quick. Large teeth are design to cut large wood and remove a large chip from the kerf of the cut. Smaller toothed saws are used for smaller, more precise cuts that require a high quality finished product. Tri cut teeth and laser cut teeth help ensure that teeth stay sharp for the life of the saw.
Different shapes also allow the climber to perform different tasks with each tool. Blades with a curved shape to them are designed to cut quickly while staying in the cut. Straight blades are made to make high quality cuts on ornamental trees. Straight blades also help when finishing the back cut of a notch with your handsaw. Since the blade is straight the back cut will be straight as well where a curved blade would leave more hinge wood in the center than at the sides. Some blades are extremely skinny to allow the climber to cut in tight unions where a standard saw wouldn't fit.
Scabbards and grips also factor into choosing a handsaw. Some grips are made of wood while others are made of rubber coated plastic. These work well by increasing the grip on the saw while cutting. Wood grips work well at reducing weight and being more cost effective. Scabbards easily attach to the side of the climbers harness while others attach to the lower leg of the climber. Leg scabbards are convenient in the fact that they stay in one place, opposed to one attached to the saddle that can flip over and upside down.
Over all, our handsaws are an extremely valuable asset to any production climber. Each one has a different use and each component of it will help in determining which saw is best suited to your personal taste.