Im interested in a backpack too.
Here is a review on the droneguard bp 450 aw Lowepro doubles down on Drones with the DroneGuard BP 450 AW
I am worried its a bit to big and bulky, and most of the time ill just be pulling up at of my car and walking less than 50 meters to a park bench.... but it does look robust and they mention in the review to get this over the go pro one (which is similar to the chinese ebay foam ones)
I ordered one of those last week - should be arriving tomorrow. I wanted one that would be good for longer hikes, and my GPC is not great for that. I'll report back.