If anyone is looking for a cheap way to protect their new Karoo 2, then I can wholeheartedly endorse the Pelican Micro 1010 Case ($13 USD on Amazon). There is about a 2mm gap between the Karoo 2 and the rubber bumper insert that comes with the case. The lanyard fills that gap. Even without the lanyard, there is almost no movement of the device if you were to shake the case back and forth. You would need to insert a piece of foam in the lid to prevent all movement of the Karoo within the case.
I used a Micro 1020 for my Karoo 1.