I would consider O-Ku the more upscale sushi restaurants Charlotte has to offer. The atmosphere is definitely classy and the service was great. I do understand the vibe they are going for with the very low lighting but it was a much in my opinion.
The sushi was all delicious and the rolls were large. I would recommend the spicy tuna roll. The prices are higher than most sushi spots in Charlotte but you are in a classy atmosphere and receiving superior service. They do have half off rolls on Monday and Wednesday if ordered during happy hour.
It gets quite crowded so I would recommend getting a reservation. The parking lot is small and a pain to get in and out of. They do offer valet parking.