The Tales of Adventure: One Retainers Journey is used to get one of your retainers up to level 60(NOTE: You require the class you are having your retainer go to 60 already at, or above, level 60).

The gears on the mog station replace the look of your armour, so they will be as you see them in the previews there. No other armours in the same slot(chest/arms/leg/head/feet) will be visible if you decide to glamour one of those on.