I have made several OBW quilts and prefer the hexagon. It is fun to turn the triangles and decide which design you like best. With the Octagon you can only place the points together one way. I also found the extras square placement a bit of a challenge having it blend with the Octagon blocks that are next to it. For your first do the hexagon. If you enjoy it, then try the Octagon and see if you have fun with it too.