The prep knife is perfect for smaller cutting but is a go-to knife for a lot of people because of the shorter, curved blade.  It also has that true Asian edge making it razor sharp.

Kaizen II is an authentic Japanese knife; much of the process is by hand.  It is made from FC61 steel which is very hard (think great edge retention) but also extremely durable (very chip resistant).  I don't believe anyone else is using this type of steel.  The beautiful 64 layer 
Damascus design protects the core of the knife as well.  The handle is authentic to Japanese heritage also, with its D shape design.  It is extremely comfortable in your hand and is made of micarta which is a linen and resin mixture.  It has the look and feel of wood, with the durability of a synthetic material.

Miyabi knives are made and sold in Japan as premium knives.