I have pked for some time and continue to when I can. I have played all types of characters.
When I compare mage vs missile pking - I find pking on a mage much more of a challenge, and more enjoyable.
With that said my main has been my bower for 6+ active years or so. And I LOVE bow. But I would say it is better for pvm for many reasons.
Bow is very weak in pvp when against melee (shield up). A melee would have to be completely noob or ungeared to die to a missile. And it is not difficult to dodge arrows as a mage - even without missile d. I have never died or can not recall the last time a missile character has taken me out 1v1 on my mage... And my mage has NO missile d.. But with that said a good missile pvper can also be very hard to take down. A good pvp mage vs a good missile usually = a really long battle.
But there is no reason you cannot mess around with both

Maybe create a unique template like xbow + void. I find my void + uaer dominates with ease. Overpowered really.
Check out some of my pk vids @
http://vimeo.com/hotshot/production - there is a bow vs mage fight in there somewhere... Along with other templates - mages, melees, voiders, etc.
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