Book 4 was my favorite. And sadly, having reread and finished the series, none of the laters ones are able to push it out of the way - or even really come close. The last ones were decent, but I think Sanderson had a fundamental misunderstanding of Matt and how the Red Hand interacted with him. Plus there were so many threads that Jordon added that got wrapped up, but didn't get made feel like they were required enough to be included so they feel like filler in a series that was way too long already. I realized that I would never again want to reread the series and gave it away.