Re: normal ww barb or IK ww barb?
It depends on what you're interested in.
For PvM purposes, I would think that the IK barb is very capable of doing anything you might need him for (rushing, mfing, etc). Plenty of survivability and dmg output imho. Then again, if you have the wealth you may want to look into bigger and better items like deadbeater suggested, because IK is certainly not the most power/damage oriented build you can make.