Opinion on the book "Invitation to the Middle Ages"?

I recently found a copy of Horst Fuhrmann's "Invitation to the Middle Ages" in a bookcase. I'm interested in the topic, but I know that even supposed "experts" are incredibly fond of spreading utter nonsense about the Middle Ages, and the worst clichés are presented as facts, falsely reinforcing the impression of the oh-so-terrible "dark" Middle Ages.

So before I start reading this book, I would like to get some outside opinions.

Thanks in advance!