I enjoy the cardio and strength combination of the work outs.
I would suggest increasing the number of classes in the studio. In particular, I think a 8 or 815p class M - Thursday would be well attended, along with a 7pm class on Friday evenings. On the weekend, some classes in the afternoons would be great, as well.
I really liked Brendan's personality (bonus points for dressing up as a gnome for Halloween!). He was very attentive in making sure each person was doing their workout correctly and also, in answering any questions.
I liked the heart monitors, and I liked that I could just look up at the screen to see my heart rate/splat points. I also liked the circuit-style structure, so that I didn't get bored with any one activity.
I like the feeling after working out and feeling like I pushed myself to the max. I also love when the coaches are energetic and keep me going. Lastly I love that they keep an eye on everyone to make sure everyone is going the exercises properly.