Yep... Reading Dan Brown is like what I would imagine having a con artist round for dinner would be like; You have several hours of intense conversation then you wake up the next morning feeling slightly dazed, realise the conversation was actually totally inane and find that they've walked off with all your valuables and left a pipe-blocker in the toilet.
I've only read the Da Vinci Code, because there was so much hype about it, I wanted to know what everyone was reading and going on about.
They were page turners, I'll give him that, he does write in that quite gripping way where most if not all of the chapters end on some kind of cliffhanger. Which is a bit annoying if you're in the habit of reading at bed time, and you're used to getting to the end of a chapter and putting the book down, because you end up thinking, Ooh, wonder how they get out of that, or wonder what that means? Just one more chapter... just one more... and before you know it it's 4am in the morning.
But.
BUT.
I did find other aspects of his style intensely annoying. I got the feeling that a lot of what he'd written, some of the descriptive stuff about buildings and places, didn't move the story on, and was completely superfluous in terms of story telling (or maybe some detail was there as a red herring so as you'd be wondering about it's significance?

). I just got the feeling that a lot of the detail was thrown in to justify tax write-offs for holidays: Dear Mr IRS man, yes, I know I'm claiming my holidays *ahem* visits to Italy and France as business expenses, they were research trips, they were essential to my book - see, I wrote about them! see! I wrote about those little statues in that chapel, I wrote about what that quaint little town actually looks like! - so they were a legitimate business expense and thus should be offset against any of my earnings.
And I found that off-putting, as if some of the writing was there for some other purpose, i.e. justifying his research trips or business expenses, instead of being there to take the story forward or for the enjoyment of the reader.