What is your opinion on Dan Brown novels?

Brown's Da Vinci Code was one of the first "proper" novel I had started with when I was a kid. I liked it enough at that time to buy his other novel, Angels and Demons soon after that. His books are usually categorized as Historical Fiction but you also wouldn't be wrong in calling them Realistic Fiction I think. Needless to say, massive controversy also surrounds Brown just like many other famous authors. At least /r/books is filled with many posts filled with both love and disdain towards this author!

What do you think about Dan Brown novels, have you read any of them?