I voted Intensity series BUT I really should have asked what you already own and if you wanted more cardio or more weights.
I feel BB has more cardio variety in it(SB - step, SJP - step & hi/lo, KPC -kickbox cardio). Also MANY premix options. You also get tow shorter total body weights with premixes for splits or longer total body weight workouts, cardio & weights, great kickbox & lower body circuit, great lower body workout. There is a nice ab routine at the end of KPC and SJP and some ab work in PP and SS.
The Intensity series has more step cardio but less cardio time overall, I believe. You get a fun interval cardio, Cardio & Weights (easier than SJP) with a great ab section at the end, BC (though cardio & weight workout with nice core work), the pyramid workouts which can be used for endurance or take extra rests or do less sets and use for strength. Awesome stability ball work in the pyramids. You also get ME, a total body endurance workout with another KILLER ab section. Great premixes althogh not as many premixes as in BB and great music, but no music louder option as with BB.
Angela:7