Keeping Loyalty
Location
Required Items
Rewards
What the allowance actually buys
One allowance here buys 418,970 EXP, which places it 3rd of the 3 Lv 78 Blacksmith tradecraft leves that record EXP. The best of them, Bae Blade, returns 1,103,750 EXP for the same allowance, 163% more.
On whether to wait: the best Lv 80 Blacksmith tradecraft leve returns 1,355,750 EXP per allowance, 23% more than the best on this rung, while the Lv 76 rung behind tops out at 1,256,820 EXP.
At Lv 78 this data holds 27 leves paying EXP across 2 categories: the 24 Tradecraft ones average 955,432 EXP per allowance, the 3 Fieldcraft ones 2,129,178 EXP, which puts this leve 56% below its own category's average.
Dwarven Mythril File ×1 is a Lv 79 Blacksmith recipe, 3 steps deep through 3 intermediates, costing 14 units of raw material and 35 crystals.
Handing that in returns 29,926 EXP and 125 gil for every unit of raw material the order swallows, and the tree needs Blacksmith and Weaver.
The record carries a repeats value of 2. This site reads that as 2 further turn-ins on the same leve — an assumption, because the source data defines no meaning for the field — which would put the ceiling at 1,256,910 EXP and 5,241 gil for the 1 allowance it costs, or 1,256,910 EXP per allowance.