Ok, I'll admit it -- I caved and got all four. I've done two so far. They are good workouts that compliment Cathe nicely, I think. As I've already told some others, I wasn't sure how to classify these, really, but I'd guess you'd put them in circuit. The hour definitely moves quickly, I think I was sore the next day, though it was hard to say if it was from Dove or from some "BrushClearing Max" I did. I definitely had that sort of shakey feeling immediately post-workout. I ended up buying a second set for my sister who is wanting to get back into shape but I think would be intimidated by Cathe's workouts at this point. I was a bit worried about Dove's workouts being injury-prone, since she moves at such a fast pace, but as I did them, I did not feel that way.
There are more reviews and some breakdowns of at least a couple of workouts over on videofitness forum. You can do a search for Dove. Let me know if you have any specific questions.
-Beth