I just can't bear being barked at! I hate classes.
Having said that, I have been doing the Reebok Core classes once a week. You stand on this tippy thing and do stuff. It works the abs like Pilates, and I have such lousy balance, so it's a challenge. But the insturctor is a guy and he's not real perky (at 7:30, I'd strangle anyone perky).
I go for the calf raises and at 220, it works.