In short: Reached by Ally Condie is a satisfactory conclusion to a decent series. 
 I loved Matched when it was released. The world building fascinated me and the writing was exquisite. Its sequel, Crossed, was when I fell out of love with the series. It was at this point that I became a bit frustrated with the lack of any interesting plot, as well as the lack of character development for the main players. Still, the writing was just as beautiful. Unfortunately, Reached is much the same as Crossed in that the plot is boring and even with Xander's point of view added into the mix, I never formed much of a connection with any of the characters. But I still appreciate Ally Condie's poetic writing. 
 Just like with Matched and Crossed, Reached is a very slowly paced book. The slow pacing worked for me in Matched as I loved the time that was put into the amazing world building, but I began to lose my patience with it in Crossed in which the slow pacing was emphasized by a lack of anything particularly interesting going on in the plot. With Reached, it's much the same as with Crossed except instead of 350 pages, it's 500 pages long and all the more boring for it. There was a lot of medical jargon and info dumps that didn't really help matters. As readers, we expect and hope series finales to out with a bang. Unfortunately, very few scenes of significance and impact actually take place in Reached. 
 One of the most important things with the last book in a series is that your questions get answered satisfactorily. In this way, Reached was a success, I suppose. Overall, Reached was a passable conclusion to a decent series that I had unfortunately fallen out of love with. I would recommend Reached to those who have read and liked Crossed as it had a similar feel and tone. Though I was disappointed that the series went out with more of a whimper instead of a bang, I am glad that I saw it through at least.