Again, it is situational.
Tengu Set is good for leech, but makes it so you need to actively use Green Potions to deal with status effects.
Imperial Set is a nice all-rounder that gives pretty much everything you need; just not optimal on faceworm but you can do it with it regardless so eh.
Mob Scarf is great because it lets you use slotted mids, which is perfect for most builds since you can roll status immune cards, engkanto, LK or Kiel (for that sweet maximum RC damage).
Seraphim is a poor choice for GX, it really -_-s you over with your stat points.
As I said, situational, but the clear loser is Seraphim.