They seem to be nice quality, but time will tell.  When assembling, make sure you put them together exactly in the order as written and loosely attach each nut to the bolt so that the other bolts will match their respective holes.  I am 6' 1" (200 lbs), and the chairs are comfortable and oversized relatively speaking compared to other patio chairs.  The back is high, even high enough to rest my head, albeit looking at the sun.  Overall, I'm very impressed so far.