Nothing really, Google knifemaking and you can find at least 30 suppliers of blades and handle making supplies. The blade material available ranges from Damascus steel to high tech stainless and handle material ranges from ivory to exotic hardwoods (and pine I suppose). RayWay only offers the one blade design and IIRC, only one material combination for the handle. I have made many knives in the past 30 years; starting with blades I hand forged and tempered to the factory-made blades I now use. There are many better options open to a potential knifemaker than the RayWay kit. Shop around a bit and I think you will agree.
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May I walk in beauty.