I used truecar (through overstock.com, I don't think overstock uses them anymore though) 2 years ago to buy a sonata. It was a great experience, and quite a lot off sticker.

Zero negotiation, walked in with the paper, that's the price of the car.

I don't think you will get the deal of the century through them, but you'll at least not get screwed. Just don't let the dealership nickel & dime you on protectants & floormats, etc. If they can't honor the exact price, just go somewhere else.