Which is efficient of Zeus sword and Adv. Imperial Gear?

[may94]

Zeus Sword's upgrade socket is 2
Adv Imperial Gear's upgrade socket is 3

I think Zeus sword is better than Adv Imperial gear.

but, small upgrade socket

What is the reason?

[Tauriel[S202]]

because in the future you might want to uprade zeus to advance? (we know this is possible, due to one event where some people got advance chaos ring).