The colors of this are so fantastic! I do most certainly love them C: They amongst my faves. Cool angle too. This is a really epic commission they got for sure! The background is a really neat touch too and its amazing how these two subjects can be so similar in color and yet stand out so differently from each other.
Well, I look at it this way: they had to do it. They needed to shock the audience when Sentinel went rogue and give them a visceral blow to the gut so we culd share in the emotional impact. Ironhide was the only Autobot aside from the cash-cows Optimus and Bumblebee who had any characterization and thus was the audiences' favorite. He died because he was awesome.