For a $1000 rifle I don't think you could expect any better than what the guys are showing, about 2 moa is a very reasonable group for a rifle with a $200 barrel. I've owned black rifles that cost me $3000+ that wouldn't shoot a 2 moa group with cheap ammo and I didn't feel that there was anything wrong with it. Ammunition choice is just as important to accuracy as a quality barrel is, without both there will be no 1 moa or sub moa groups.
AR barrels will fit so your accuracy potential is the same an AR and pretty much dependent on how much money you're willing to spend. Just need to find a non restricted length barrel with gas port in the right spot. I think these have a carbine length gas system if I recall correctly which will make finding a barrel harder but not impossible and there is always the custom barrel option if you want accuracy from it.
Still not sure why so many people seem to think that a $1000 rifle with the cheapest barrel they could source (in order to keep the cost down) should shoot tight groups like a $2000 AR. You're buying an entry level fun gun that was brought to market because there was a gap in the affordable decent non restricted black rifle category. It seems to have filled the gap nicely and put rifles in the hands of a lot of guys that otherwise couldn't afford a non restricted black rifle and also given some of the more experienced guys without the budget restraints a nice little fun gun they can bash around a bit and not cry about if it gets a scratch.
Barrel break-in? Why? Is it going to make the groups smaller? Is it going to last longer? Is it going to do anything other than be a really boring way to shoot your first 20 rounds?
Just shoot it, it comes with the cheapest barrel they could find, I wouldn't worry about it at all.
Beltfed,
Is that target marked 2007? Hmmmm....
There's a break in procedure?
Yes,
Step one, fill magazine with 223/5.56
Step two, insert into magazine well of rifle
Step three, Charge rifle
Step four, while pointed in a safe direction pull the trigger repeatedly until it stops firing.
Step five, eject empty magazine
Step six, repeat steps 1-5 until you're out of ammunition or it gets dark.
Your barrel is now broken in and ready to shoot into space.