Mostly enjoyed Fall of Giants: Book One of the Century Trilogy for its detailed narration of societal shifts pre WWI, the lead-up to the war and the war itself. A good way to get a feel for how it came about. Especially as WWI for me never got much attention as the Netherlands remained neutral during it (the big 1914-1918 story we were taught concerns the up to 1 million Belgian refugees, and the POWs fleeing across the border / being repatriated through the Netherlands during the flue pandemic)
Many characters are more caricatures, and many dialogues meant to explain some strain of reasoning that influence how WW1 developed are rather simplistic.
Follett is one of those authors that has hit upon a well working template for his books, and then re-uses that time and again. Good amusement though.