Rather than review each of the individual books, I'll just review the series as a whole now.
It was pretty good, but it did have a few problems. I don't care overmuch about world-building, so the fact that Osten Ard is a fairly standard world didn't bother me much. It was still interesting. Characters and story are what I care about, and Memory, Sorrow and Thorn had plenty of both. The pace does drag a bit here and there, but for the most part it keeps moving along. The beginning of The Dragonbone Chair didn't have much action, as many have complained, but it was still good. I certainly wasn't bored for the first 200 pages or so, but then, I've always been a sucker for exposition. Really, my only problems are fairly small ones, in the scheme of things:
1)Characters, most especially Simon, pass out way, way too much. It seems like once Simon is on his quest, he passes out/is knocked out at the end of every chapter he's in. This isn't exaggeration, at least not by much. The others do it quite a bit as well, but none so much as poor Simon-boy. After the first dozen times, it gets pretty grating.
2)He switches perspective way too often. I love this device, it's great for creating tension, and maintaining suspense, as well as not letting any of the characters fade too much from memory. I use it myself, in my own writing. But in this case the perspective shifts way too often. By the time you get to the third book, hardly an entire chapter is spent on a single character. Usually, a single chapter splits into three or so different characters' stories. Just as you're getting interested in one, you get dragged into another character's storyline. Then, when you're just getting back into that storyline, lo and behold, you're pulled into yet another one. All the storylines are good, but none of them get lingered on for long enough. It does create tension, but when overused (and misused, in many cases) it's just irritating.
But, excepting those two things, I didn't really have any problems with the series. All in all, it was a fun, emotionally involving work, and I'm very glad I read it. You should too. At least the first book, to see if you like it. But even if it seems you won't like it, ACTUALLY FINISH THE FIRST BOOK, not 3 chapters, not 200 pages, not 3/4, FINISH it. Chances are, you'll be glad you did. NO book is good when left only half-read.