I have very much come round on the later books. I - like most people - didn't much care for them on first reading but I love them now. While they still have some epic 'wtf' moments*, they are dense and are generally more concerned with the characters internal struggles and dilemnas than they are with exciting plot twists. They also include very important character development for Dany and Jon who, having both ascended to power in the previous books, now have to grapple with the politics of ruling and attempting to win the peace (and both failing in their own ways).
A Feast For Crows and A Dance With Dragons, taken together (they were originally intended as one book) are also quite deliberately slower paced to represent the lull between the cataclysmic events of the opening trilogy, whereas the intended next book (The Winds of Winter) will see things gathering pace for the big finale (for a start, it's opening chapters will essentially comprise two giant battles). They aren't page turners in the same sense, but I very much disagree with the common opinion that Martin has 'lost control' over the narrative. I fully understand why some people struggle with the Dorne and Iron islands plots in A Feast for Crows - I did at first - but there is a lot of meat on the bones and the books are well worth revisiting.
Having said all that, I totally understand the need to pare them down for TV adaptation, I just think the TV show writers have badly floundered in how they have handled things, especially concerning Stannis and the farcical Dorne storyline.
*Like the Daznak's Pit scene (where Dany escapes from the Gladiator stadium on the back of Drogon) which imo the show totally bungled and is so much cooler and frankly more metal as it plays out in the books.
