easy said:
if u have to kite aoes or get knockbacked sometimes a bow is better cause u shoot boom 3-9k crit and go in melee again
if u have a long ranged fight, pouches do better cause they hit more often, believe it or not i tested it on milyex :D
i use atm a pouch cause mine hase int, more str but less hp then rigid scale bow and i dont use often ranged auto attack... basically never cause i stay in aoes with sta 4-4-8 and about 12-13k hp in raid + i stay at walls when knockback mobs like protectors realm are incoming
