It depends on what you're doing. For combo/agi builds, maces are pretty fail since they're slower. The only real benefit for a mace is that it's unbreakable. That doesn't matter in PvM, and combo/agi builds aren't that great for PvP or WoE, so... you do the math.

Of course, Waghnaks are no longer the only 4-slotted claw/fist option. I forget the name of it, but there's a new 4-slotted claw/fist weapon that came with the update. It's pretty badass and makes Waghnaks pretty worthless by comparison.