As of version .35, I have found that any bows are severely underpowered by what their vanilla mechanics should be. For example, a normal vanilla bow can shoot 15-41 blocks depending on the arc, but any bow will only achieve 2-3 blocks at full draw. Additionally, arrows fired from bows have a high chance of not interacting with the target correctly and will instead float in them and spin around in place (this was found after attempting to fight the warden). Because of this, all bows in the pack are functionally useless against mobs, especially against bosses like the warden. Note also that power enchantments do enhance the range of the bow but still only to a degree that is far below what a vanilla unenchanted bow could do.