I highly recommend Honda of Concord and the Hendrick Automotive Group in general.
My wife and I recently purchased a VW EOS Convertible from Honda of Concord. The sales staff was friendly without being pushy and overbearing. The purchase process was efficient and we were on our way in short order.
About two weeks after purchasing the car the headlights stopped working. The car had just over 36,000 miles on it so it was no longer covered by the factory warranty.
We contacted the sales manager and they immediately stepped up to take care of the repair -- without an argument or a debate. They completely reset my expectations when it comes to buying a "certified" / used car.
These guys are honest and reliable, be sure to at least stop by when it comes time to buy your next car.