Alright so as the title says, the 3x rings actually decrease your EXP
check this:
Without 3x ring
With 3x ring
DOUBLE CHECKED
Without 3x ring
With 3x ring
Now unless its a graphical error [ the blue text misleads sometimes but the TAB is always accurate. ]
I killed her the exact same way twice.
fix your rings or give a refund if this is indeed the case with the 3x ring.