You took the words right out of my mouth!
Get both!
I got MIS first, and although many feel it is partially an endurance workout, I don't get the same results from Mis as I do from PowerHour, which is an endurance workout.
I use MIS as a "heavy" lifting video and go very heavy with my weights. The pace is faster than S&H, but much slower than PowerHour, so I utilize MIS as a "strength/mass building" workout and PowerHour as an endurance workout with lighter weights.
So, yes, get them both, they can be used separately or together in a rotation, they are a great change of pace from one another, afterall, your body does need to switch up workouts after a certain amount of time, so you'll use both and love both for different reasons.
Have I spent your money yet?
Donna