A crafted one handed sword at blacksmith 5 gets either additional damage or add. may. action points, can be sharpened and enhanced with a tormented soul.
According my craft history a legendary or unique usually beats a self craft at level 5 BS only and so far as the additions (stun, cripple, burn etc.) are useful.
After some hundred hours of play I would rank weapons like unique > self craft BS 5 > rare > self craft BS 3 > magic > common.
Particularly for bows the self craft at CS 5 can be better than anything else, if you enhance it with a bowstring, a telescope and some essence/tenebrium etc. My rangers damage output at level 21 was with a self crafted bow rated between 350 and 550.
Biggest advantage of crafting is you can fill gaps for specific weapons where the last one found good was say level 7 but your characters are already level 11. You will mostz likely find something better in the future but you can fill that gap with a self craft in between.
Regards,
Thorsten