Seems to be a pretty good deal for $600. For a little more you can do better. It all depends on what you want in an AR.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
You'll remember the quality of a gun long after you forget how much you paid for it.
US Army 1966-69, VFW Life Member, Retired Geek