I really like 9Round. It's nice to have a gym where you can go in and basically do your ish and leave. There are nine different stations with varying equipment, and the activities are different every day. You do intense cardio for three minutes and then one minute of "active rest" like high knees or wall jumps, and move on to the next round. It's only half an hour but the intensity of the work makes it feel like a full hour by the end.
The instructors are attentive and help each student perfect their technique during the rounds. I have kind of a bum ankle and talked to one of the instructors about it and he gave me a suggestion for how to approach certain kicks. He said, "if this doesn't work, we'll find something that does work." It's the first place I've been where the instructors care enough to help and actually follow up with their students. I'm pretty sure the first workout is free, so if you've been curious about it, you've got nothing to lose. Go ahead and give them a try! You won't be disappointed!