His main drawback is the 15' speed (iron body halves your movement rate), which is why I gave him Heroic Surge. Even so, he can only use it 4 times a day. When he does manage to catch someone, he can use Power Attack for, say, 4 pts, and if he hits (+17 base +2 charge -4 PA = +15 to hit), it'll almost certainly force a massive damage save (15-20 damage). With Great Cleave, he can lay waste to massive hordes of ordinaries (as he appeared to do in the last issue of Planetary), providing he can catch up with them.