Looking at the vids of O'Grady's goals, the ones he scored with his head look like tap-ins. He looks like a big strong player who can hold the ball up but I doubt we're going to see the type of difficult headed goals the likes of Zamora, Murray and Ulloa scored. I don't think you have to be big...
Ulloa is an absolute legend in the box with his head. I lost count of the number of wasted crosses into the box that went by unclaimed in the period between Murray & Ulloa. Hopefully we get someone good in the air, COG is not the man to replace that element of our game.