General

Wait for Empress shoulder

I have both, so far its on normal mobs use dojo gloves, on bosses use set.

emp does more dmg, vs normal mobs and has 5%more boss dmg...any1 that said mu gongs was wrong lol

Mu Gong gloves are better if your empress gloves are clean. (Even if it removes the 6 set effect with 30 attack and 30% boss damage)
Benefits of Mu Gong Gloves.
+25% bossing damage
+15% total damage
+15% all stats
+25 all stats, +15 attack/magic att

The 25% bossing damage and +15% total damage already makes up for the 30 attack and 30% bossing damage from 6 set empress.
Empress Gloves DO have the potential to be better though. (Fully scrolled, with A LOT of % stat potential/decent sharp eyes/decent SI)

Mu gong gloves are better than empress anytime, even if that means that you lose the 6th bonus, even So gong ones beat empress on most situations.

That unless your empess gloves have 24%+ on your main stat.

Empress.