Those You-Finish kits are fine ways to learn the tillering aspect of bow making and get yourself a shootable bow relatively quickly for a reasonable price. For only slightly more work and time and quite a bit less cost, you can do essentially the same by making a board bow with a red oak or hickory board from you local hardware store, or from almost any sapling or young tree behind the house, depending on your area. But, as you probably know, the more raw material you begin with, the more time and effort required to get the bow. With that in mind, those kits are excellent projects.