For right now the challenge is coming and some have gotten there new gear. If there is a duel between now and the start of the challenge, can we use the weapons and armor we picked?
That would be in the hands of Derhlith. But it'd be quite odd for that to happen. Though.. Mage's and Cleric's alike were given a favor and were allowed to use weapons that they couldn't have. So its a possibility, but I still highly doubt it.
Sad to say, no. If you were to duel between now and the end of the event you'd be using your standard gear. Simply because the gear came from Helineth and there's no telling if you would have it after the event. Alongside the fact that some people are using gear they may not actually be permitted to use. I still need to bug Baerholn about that when he gets back next week.