That whole "properly melded crafted i170 is better than bought i180" cannot apply to Gathering gear. And yes, there is a reason it not only does not, but CANNOT apply.

There is no crafted i170 counterpart to the bought i180 Gathering gear.

Maybe its coming with 3.10 .. who knows. But for right now, and for the next couple months, you have a sick and twisted choice : use Red Gather Tokens for Favors to make Crafting gear or general Gathering gear, or to use them for the class-specific Gathering gear.