IMHO, in descending order of intensity (cardio):
1. The 10-10-10 workout (the hi/lo segment has 4 blast-your-butt-off intervals that are awesome);
2. The Power Circuit workout (hi/lo followed by 20 minutes of step- and step-kickbox cardio with barbell and dumbbell leg circuits);
3. The Step Interval workout (ends with 10 minutes of intervals);
4. The Kickbox workout (has some great lower- and upper body conditioning drills and a nice extended interval of "power scissors", what Cathe now calls "explosive lunges"); then
5. The Allstep Workout.
Re the upper body strengthening and the Leaner (Meaner) Legs routines, I'll leave that to others to discuss.
The ab sections, well . . . the Kickbox core and ab routine and the Leaner Legs ab routines are ab fab!
HTH -
A-Jock