Paul
Welcome to the forum.
I've read the book you mentioned three times now (I think, it might have been four). To be quite honest, I don't know what to make of it, or any of the other literature contra Fr. Seraphim. For instance, one consistent charge that I see made against Fr. Seraphim is that he distorted or deceptively translated/quoted texts. The problem is, I am nowhere close to a place with a substantial Orthodox library, and I can only read English. So, I have really no way to verify this either way. Not wanting to judge Fr. Seraphim, I hope that maybe he just used a different translation, or a paraphrased version, or something like that. I have no way to research these types of charges, to find out whether someone is definately correct, whether someone is innocently mistaken, or something else.
I have also struggled with the polemical style of the literature contra Fr. Seraphim, though that probably has more to do with my being raised in an ecumenically-inclined, politically-correct society; nonetheless, regardless of the source of my problem in that area, it does remain something of a problem. Another problem I have is that I disagree with some of the other positions taken by Fr. Michael, such as his stance regarding Augustine, so no matter how hard I try to avoid it, I probably have a less than perfect "association" when I read his works. Some people have suggested other works of his (and others) though, and I still plan on getting those and reading them.