The 2010 Kia Rio has a higher rated EPA mileage than the 2009 model that I have. I've not taken a road trip in my 2009 yet, but in mixed small town / rural 2-lane highway driving, I consistently get near 40 / over 40 mpg. Worst tank to date is over 37 mpg, best is 41.86.
Mine is the SX model with a 5-speed. AFAIK, I believe the automatic is rated 1 mpg better than the manual. I'm pleased with the quality of the car so far.
According to the brochures I read, the base 2010 Kia Rio comes with manual windows, locks, etc.....and no air conditioner, not even as an option. In my neck of the woods, that rules the base model completely out. The person who dreamed up the expression, "It ain't the heat, it's the humidity" lived in the southeastern United States, I'm sure.