One of the features of the MINI that made it seem possible to be able to safely transport children was the fact that it is specifically designed for the LATCH system car-seats. We had used my mother's and my brother's MINIs on occasion with our son and their cars were the easiest ones hands down that I have ever had to install the base in.
Somehow, we found the perfect MINI for our little family- and we all love it! Not having to get a new car-seat was a plus as well. I definitely recommend getting the Baby Trend Flex-Loc if you are considering a Rear Facing Car-seat for your infant and you drive a MINI Cooper or Cooper S. The triangle handle shape comes in "handy" when moving the child in and out of the little two door car, and it has a number 1 safety rating. It's an all around great seat!
Baby Trend Galaxy Flex-Loc Infant Car Seat
Baby Trend Galaxy Flex-Loc Infant Car Seat