Updated with information on Excellion gear and enchants.
By themselves, these armors are defensive options. High DEF, VIT bonuses, bonus HP and Perfect Dodge. But no slots.

You can then enchant them, and these can be worn by any class. It's all done by farming monsters in the Verus region. Up to 3 per piece, although there are some limitations. Some can only go armor, some only on garment, some can be applied just once per piece.
You can get up to 45% resist for Fire/Water/Wind/Earth on garment, +1 ASPD on both pieces, +37 ATK on an armor, or supercharge your HP/SP recovery. At the cost of card slots, of course. Or any combination you like, as long as it respects the stack limits...

An interesting thing about this system is that the enchants are a tradeable item. If you get something you don't want, you can trade it with another player or sell.

I feel that these may be a little overtuned, it's a lot of bonuses...still need to test. But I do like the variety in enchants.