The first 3 books are pretty good. Only with hindsight, if you
do read them, don't expect much after that. Once you get into the series, you really want MORE, and the more is not forthcoming at all. I will say that the sexual situations in the first 3 books are more normal and less titillating than the TV show.
The cruel and raunchy stuff is really unpleasant in book 5. I really didn't get the impression of alot of "sex" from the first 3 books. But I did get that big impression of eroticism etc from the TV show. Perhaps that is the intent to snag more viewers? The TV show likes the nudity factor too!
For example, in the books, Dany's encounters with her chieftain husband are VERY different than portrayed on the TV show. (including the "honeymoon")

The books are very very long... lots of reading too. Almost 1000 pages each. So they can be engrossing and interesting. It is just a bummer that the cliffhangers become very numerous and have no resolution really.

I've become very disappointed in my other favorite authors.
(Oh, and I forgot Anne Rice-- her later books are off my list too). This series really made me angry because so many others I've liked over the years have stalled out or had major difficulties. I read the reviews at Amazon sometimes, and I am not the only one having these feelings... there are many other readers chafing at some authors. But Dance with Dragon has almost 400 negative reviews now! That is the most I've seen except for Pat Cornwell.