Been doing the Body Pump for three weeks now. It's killer. Burns over 700 calories each time. The first time was difficult and I kept having to stop to catch my breath or stop my muscles from screaming at me, but now I can last pretty much the entire 1 hour workout only stopping two or three times. Pretty soon I'll go all the way.
The Body Combat appears to be too much high impact for my knees. I do like several of the cardio boxing moves I saw the class do. Maybe later.
Body Flow looks like yoga/pilates stuff. Not my cup of tea.