What Weapon combo?
Tbh, WvW on low lvl is nothing similar to lvl80 WvW, the only pvp you gonna get as low level is running around with a shortbow in a zerg trying to tag as many enemies as possible for loot.
At 80, you will be able to roam freely outside the zerg safety zone, and when you do that, you will be killed by me and many other thieves no matter what your weapon is.
To sum it up, lowlvl in wvw, just bring a shortbow and follow commander, and at 80, get to 80 before worrying about that.
Thief.