My take...I like your enthusiasm but, based on the questions you've asked I'm guessing you haven't much experience. That being the case a bamboo backed bow is, in my opinion to advanced. Get a good straight board, or better yet get a good straight stave. Either way you choose, build a good solid self bow. Doing either will teach you the basics of this craft. Back it if you are so compelled with rawhide as it is a fairly easy process, but a backing of any kind wont fix a poorly made bow, and a well made bow wont need a backing. Tackle the boo backed Osage down the road a piece. Just my thoughts.