A lot of comparison has been done in this thread -> http://www.tankspot.com/forums/f97/5...ses-worth.html
I'm not even going for the T10 until I have all the other badge pieces that I want. Pillars of Might brings a whole knew meaning to the words, "Thunda Thighs." I'm totally picking them up because they're phat. Get it? hur hur. Seriously though they're awesome imo. However if you have the Jaraxxus 258 legs, then you might wait on them and not have them be the first piece you upgrade.