I ended up ignoring the included assembly directions, which seemed very awkward to me.  I found it much easier to loosely bolt the legs to the seat, insert the stretcher bars with a dab of wood glue in the holes, tighten the bolts, and finally screw the stretcher bars in place.  Once I figured that out, the chairs went together quickly.  The assembled chairs are quite sturdy.  Note that the included hardware bag for each chair contained an extra piece of each different kind.  

If you haven't already seen the reviews for this set on other web sites, beware that the color of the finish is much darker and more red than is pictured.  It's basically a reddish "mission oak" or "cherry oak" finish, not a golden oak color.  That said, the darker color was what I was looking for and I'm pleased by how well the set matches my other mission-style furniture.  

Also, beware that the wood is not oak at all, but parawood finished to look like oak.