I read this book, although it has been quite some time ago, and I wasn’t a Catholic at the time, although I was in the beginning stages of my journey home and didn’t know it yet.
I have mixed feelings about the book. It seems to me that while reading it, something didn’t sit right with me, but I can’t tell you why specifically. I guess at the time I was getting really tired of most of the “evangelical” books I was reading that were so focused on “self”, and this just seemed to be another one in the pile. I didn’t, in the end, find it very deep. But, maybe it was lost on me, maybe it was intended to reach people who hadn’t yet contemplated the reason for their existence/creation. I was already beyond those beginning stages in my spiritual journey when I read it.
Also, Catholic spirituality doesn’t seem to be as ''self-centered" in comparison, which I find so completely refreshing. After having discovered the Catholic faith and the wealth of spiritual readings from her history, I had no desire to revisit any of the “evangelical” books I had previously read, “Purpose Driven Life” being one of them.
Sorry, maybe others here can be a little more specific “theologically” in helping you with this.