We drive to Michigan every summer. Simba sleeps the WHOLE way. He sits in the backseat nicely and there is no problem with him doing his buisness in the car he just simply waits until we have to stop. We collapse Simba's dog cage and stick it in the back of the truck. Im not sure how good a puppy would do because of the fact that he could do his buisness in the truck. Simba LOVES going in the car but he was sure glad to be home! And it was like Us and Simba took shifts... when we would stop at a rest stop, Simba would wake up and look around and we would sleep lol. Because of the bad stuff i heard that happens on plains were they put the animals... i wouldn't ever trust my Simba in there. The poor doggie would have no idea what to do. Either i would suggest we drive or refuse to go and stay home with Simba.... which ever way you choose to go to MI..make sure its safe for you and the dogs and have fun.