It would have to get OVER 49 mpg BEFORE breaking even using today's gas/diesel prices. (over the 42mpg Cruze)
That is IF the purchase price was the same. Cost more would have to better that 49mpg. Even if it did get a lot better MPG and the purchase price was the same I'd still pass due to the complex EPA garbage that diesels have since a few years ago.
It will be interesting... Anything to up that CAFE number for mother.