Honestly, this isn't a great book. I love Zuzka's workouts and I love her outlook on fitness and life in general (it's hard to believe she's so positive despite everything she's been through) but this just felt very VERY basic.
There's also a lot of anecdotal information about nutrition - this worked for her, and that's great, but that doesn't mean it will work for everyone. Hers is close to the paleo/primal diet, though she never says that, and it's very low carb (she says she keeps her carbs below 50!) and higher fat. Not exactly vegetarian friendly.
I didn't read this for the nutrition though. I read it for the fitness part. I mean, it's called 15 min to FIT so you'd think that the majority (if not all) of the book would be about fitness and workouts, but....nope. There's about 2 chapters total, maybe 10% of the book and ONE WEEK of workouts. Granted there are great pictures to go with the moves she says to do, but that's what google is for. And if you have done any of her workouts, you can figure them out.