I absolutely love it and visited three times in the first two weeks it was open. There's a broad range of work, from a prominent display of Harry Callahan's work, to individual works from Edward Weston, Avedon, Steichen, Dorothea Lange, etc; such a comprehensive collection. Only a portion of the entire holding is displayed at a time, so the gallery isn't huge by any means, but they do rotate every three months or so. I think they're due around the beginning of October. It is, however, plenty to satisfy if you're actually looking at the prints instead of doing the gallery power-walk.
Its most definitely worth the time to go see this collection! Maybe I'm so excited about it because we don't have this calibur of gallery come through Kansas City often, but I've been thoroughly impressed. Enjoy!