I'm on the part of the quest where i have the precursor weapon, and the materia, but don't have them melded yet. I was told that i shouldn't equip or use the item until it's melded, but others have told me it's fine. I pretty much spent all my gil getting these things off the Market Board, and all the crafters want 20k gil to meld them, but it may be a while before i build up to that again. The weapon is a good deal better than what i have even without the materia, so it would help me to use it, but i really don't want to bone myself on the quest for the relic.
Anyone able to give me a definitive answer as to if i can use it before melding?