Something that's pretty clear to me now. I've been noticing it more and more.
He obviously has ferocious acceleration. Over ten yards or so, he kind of reminds me of Johah Lomu. A locomotive. He is also virtually impossible to knock off the ball.
But, sorry, he's not very clever with his feet. He gets away with not having a particularly good first touch, especially, because he can accelerate and get to the ball before his marker despite it (not because of it). Sergio had clearly a subtler touch, and his control was just generally better.
Not saying one is better than the other overall, and I'm sure he's a monster who'll score a lot of goals for us. But in pure footballing terms, I actually enjoyed watching prime Aguero more.