Hi, we purchased a used 2017 QX30 this weekend from a Mazda dealer. I have a few questions. They indicated that the radio was premium sound - does that mean that it has Bose speakers? What is supposed to be in the back under the the trunk cover (not sure what to call it). It looks like a wheel and a box go in there, but nothing is in there. Does anyone know how we can confirm that run flats are on the car? The salesman did not know, so we negotiated a spare tire, but I'm not sure it will even fit in that spot in the back of the car. Thank you in advance and I sure appreciate reading the forum.