I'd never heard of Leah Remini before I heard of her Scientology tell-all. In you case you haven't either, she's a TV star who more or less grew up in the church. I guess I knew it was called "Church of Scientology," but since the practice is so unchurchlike, in that you don't worship in a group on the sabbath or celebrate a lot holidays with big dinners, that I know of, I hadn't though of it as church, exactly. In that the work of healing oneself--and the world--is done individually and in smaller groups, it's an appealing model for organized spirituality.
Remini comes across as and I don't think would deny that she is a rude, loudmouth who doesn't listen. These charming qualities are ultimately what help her escape the church's greedy clutches.
It's mostly a good read; it seems Remini's "editor" Rebecca Paley, as she's referred to in the acknowledgments (but the catalog record has her as a "with") kept Remini on track until the part where she breaks with Scientology. At that point, there's some rambling and ranting. Maybe she learned her communication style from Scientology, since their rebuttal statement reads like something Donald Trump would write, e.g., "Ms. Remini is now joined at the hip with this collection of deadbeats, admitted liars, self-admitted perjurers, wife beaters and worse."