In a word, awful. It reads like a 1930's boys tale of adventure. Patton checks a Colonel's hemorrhoids, GI's are killing German Field Marshals, and the presence of Jewish officers in the American army is explained.
It could just be poorly written fiction for there's no footnotes, and the few facts we can check are at the very least misleading. For example, the book tells us that Patton got across the Rhein before the British, by boat on March 22nd ... So? Hodges's 1st Army had crossed the river over bridge at Remagen two weeks before.
At any rate, I found it so painful to read that I pitched it after 50 pages. Which is too bad. The raid on Hammelburg deserves an engaging, yet historically sound treatment.