This forum will be permanently shut down on Friday 13.07.2018 Please copy or save all important information from old forum before they will be deactivated
We have moved to new board. https://forum.runesofmagic.gameforge.com/Come join us.
The Yawaka Guard is currently the only weapon which directly increases your aggro (with a flat percentage).
From what I have seen on my private account, it is worth the upgrade due to the fact that you greatly increase your DPS. --- Increasing DPS increases Aggro indirectly.
It would be worth it.
I do remember seeing that the ToSH normal sword being better then a GrafuHM Juggler's Sword.
If you want to see these things better in-game try getting the add-on called Item Forge and DungeonLoot to find the item you want to modify and you can play around to see what best suits you.
I think it's only slightly better than meme sword, because of sta and str ghost compared to matt and mdmg, but since mem sword is, well, from mementos, it's easier to obtain. It is also a bit better because it's faster.