The short answer is that almost no rental cars in the intermediate class come with adaptive cruise control. While the makes/models and trim levels vary by company and luck of the draw, I can't recall a single time I've seen any sort of adaptive cruise control. I have seen lane departure warning features on a few newer cars, but it's been pretty spotty. If you want to try your luck, sign up for National Emerald Club and/or Hertz Gold Rewards and rent from an airport location that has Emerald Aisle service or Hertz Ultimate Choice. The bigger the location the better as you will have more to choose from. That said, you'll have to walk around the lot and try to spot a vehicle that has the features you want, which may not always be easy.