A bound bow is on par with un-upgraded Daedric bows, so long as you have taken the Mystic Binding perk, which becomes available after taking the first perk of the conjuration perktree, and by having at least 20 conjuration.
As a side note, High Elves/Altmer basically can do this at level three, since they start with 20 in conjuration.
It's not tvery good because it can't be smithed. Other bows are much better for that reason.
Only once you reach the higher level weapons. Not sure which weapon material will surpass bound weaponry once you get the associated smithing perk. But, it's the best weapon you'll be able to get in the early levels, far surpassing any other weapon you can find or smith.
However, unlike other bows, they weigh nothing, and you don't have to worry about arrows. Plus, bound weaponry can't be disarmed. So, essentially, it's a trade off of higher damage/enchantments or not having to worry about encuberance limits, arrows, and being without a weapon. Fair trade, IMO.