Yea, I like the way he works too, considering I didn't have to shape any sort of alert, he just naturally dives into the boxes.
I got caught up and scared of his alert a few days before though because he pawed at a box slightly, and I had forgotten where it was hidden so I was all like "yay!" but it wasn't the right one. So yea, then after that for some reason he stopped pawing at boxes and just sort of looked up at me -- which is obviously not as strong of an alert as pawing or jumping on it.
He was a street dog for a while, so our instructor is always amused at the lengths he'll go to get a scent. In the beginning days when we worked with flower pots and cookie tins and the food was still paired with the birch, Baby had no issue opening the containers and getting the food out himself lol.