Was stuck on giving it either a 4 star or 5 star. Had to go with the 5.
O'Aces is a tough little spot to get to, tucked in the back corner of an office park. When you walk in, just as everyone else has said, there is a separate dining area divided by glass from the main bar. I did sit in the bar and order food there with no problems.
The food... I ordered the Kalifornication sandwich (chicken breast, avocado, bacon, jalapeno aioli, etc) and it was AMAZING. Seriously. Blackened chicken breast seasoned SO perfectly and everything jived so nicely. Perfect sized portion as well.
Came here on a Groupon, but I have absolutely no doubt I will be back!
PS. Service was top notch. Extremely nice server, I had.