Went last month with a Harlem tour group around 9pm, and it was awesome!!
I mean, it's The Cotton Club! For any jazz fan, that's a pretty big deal. I know it's not the original location, but still an amazing place where the old great jazz standards are played on a regular basis and the past is not forgotten but remembered through wonderful saxophone wailing and bluesy jazz singers.
The night we attended, the band played some Billie Holiday, some Temps (My Girl in purely instrumental) and even Chuck Berry (Solomon Hicks really knows how to play that guitar, crazy...) just such a cool night!
The servers/waitors were nice, the drinks were fine. More than anything, it was just the vibe. Dark lighting, the other people there were hilarious and dancing with each other while others' rallied them on, just a really easy-going environment to pretend you're back in the 40s.