Very disappointing. If you read the books, the first fifteen minutes of the first episode will be a complete shock.
They aged the kids to 20 (and made Nyneave and Egween the same age as Rand, Mat, and Perrin). This seemed to have no other reason than to push romantic scenes and marry off Perrin. Yes, Perrin is married when it starts. So, raising their age completely kills one of the big themes of the story where you have these kids from a culturally limited area thrown into the big world with so many different cultures and different types of peoples that are so foreign and dangerous to them.
Back to marrying off Perrin: They made him married and he killed his wife thinking she was a Trolloc, and then this Perrin in the show hid that this happened. Perrin would never hide that, as that goes completely against the character - honest and straightforward to a fault (until Faile is taken, of course). This is writing that took up valuable time and film that would have been better left out.
They made Loial super small. They made him somewhere around 7 feet. When talking about how wrong this is with someone, they mentioned it might have been because they didn't want to use effects or camera tricks, but if they spent the money on Trollocs and CGI for the weave, they could have not messed up Ogier, not to mention the B-movie level makeup they have him in.
The best part of this adaptation is Moiraine. They also did great casting with Liandrin.
I could complain for pages about details that seemed super important to Robert Jordan but were ignored for the adaptation, such as Rand's eyes. How hard is it to throw contacts on? Jordan described Rand's eyes many times in each book, which shows how important that detail was to him, but just thrown in the wind.
It isn't the worst, but the writers did not show respect to the author or his creation. If you are going to turn such a beloved story into a movie, give it the love it deserves. Phaw!