I’m the guy that wrote the “Why I Hate the AR” article a couple decades ago.  But I’ve come around to them now… after 50 years of continual development, AR’s are pretty much all decent enough now.  They all work pretty well.  But…  I’m really picky when it comes to AR’s now.   I’ll dismiss most AR’s in any gunshop.  Being jaded as I am… having seen everything on the market with little that actually impresses me… People ask me all the time what I look for.  What I look for in an AR first and foremost is Accuracy.  It’s all about that Barrel.   I want it Cold Hammer Forged.  If it’s not – I’m just not going to spend my money on it.  Period.  So I am going to look for those markings on the barrel to ID where it came from, so I can know how it’s made.  CHF barrels are no guarantee of it being super accurate – just consistent.  And that’s where accuracy starts.  With traditionally made barrels – some can be very accurate.  Others, less so.  You don’t know what you are getting until after you bought it.
CHF Barrels, takes away that variation.
I’m also going to look for a free-floating barrel.  Traditional A1 and A2 and other similar handguards that are connected at the front, are things I am going to always avoid.  You can have an accurate rifle with those… But simply gripping them differently will apply different pressures to the barrel and effect the Harmonics.  Variations in Barrel Harmonics will effect accuracy.

You know how some rifles prefer loads of different bullet weights and velocities?  Reloaders will play with powder loads to find that perfect load for max accuracy – what they are really playing with is Harmonics.

Allow me to explain.  When a shot is fired from the barrel, that barrel starts to move.  A lot more than you would think.  An accurate rifle has a very consistent movement and the bullet exits the muzzle the same place in the barrel’s movement every time.    Things that change the way the barrel moves effects this – and thus effects accuracy most often in a negative way.

I want the Upper and Lower receivers to be tight.  With as little movement as possible.  In some builds, designed for close quarters, or in AR Pistols, this isn’t so big of a deal.  A little movement isn’t going to effect anything.  But for a rifle configuration for longer range work – I want this to be a bank vault fit.  Or if this is a build that is supposedly a super high quality build… or anything north of 900 dollars… I want this to be a bank vault fit.

The other thing I look for in an AR is a good trigger pull.   I don’t care about the weight in most AR triggers.  But I want that break to be crisp and clean.  I want it to break like a hard thought.

These are the main things I look for in an AR.  Everything else can be altered and changed out easily.  So they don’t matter so much.  But what I described – that’s the foundation to build your Configuration on.