I'm thinking about getting a Sac Chien for my mini lop rabbit. I was wondering for those who have one, what size did you get? I'm not sure whether I should get the small one or the large one. My rabbit is about 8-9 inches long (laying down, but not stretched out), and I will be taking long road trips (7-8 hrs) with her and I want to make sure she is comfortable and able to stretch out in the carrier when we're on the road. Any input would help!