Man, that's a tough one. This is a hard objective to judge but i'll try to be fair here. First of all, that vehicle in Avi's stunt was a huge bummer. But the lack of backward stoppies in Diaz' stunt was too. Avi's stunt involved a backward stoppie, a coolio 270° spin and a clean and smooth grind. Diaz' stunt looked way better in my opinion but the lack of elements in it was kinda dissapointing. Technically, the only thing i can count there is that he jumped backwards and landed a grind. As i said, the lack of stoppies/wheelies didn't really scored points for me.
Again, this was a hard one but i'm voting for Avi since his stunt involved more elements.