Best in slot for value I say Palmetto State Armory. I have/had many and never an issue. Problem looking right now is getting what you want and availability is going to be VERY difficult. I am trying to build a 12.5" with handguard over barrel for a suppresor which I am ordering this week.
For factory guns that are more well known it is hard to beat Colt, Spikes, DD, BCM, LMT, Noveske, etc... But you are going to pay a premium.
What I recommend doing? Get an upper/lower combo from a place like Aero Precision or PSA and then build it with the boys, piece by piece as it comes available with exactly what you want. I also recommend fingering as many rifles as possible before doing so. That way you know what you like. A heavy barrel is great for yotes/long range but is super taxing when transitioning between mutiple targets, quickly.
Are you going to the get together this weekend? I am planning to attend one day and can bring some examples for them. 18" barrels down to 10.5" These are what I have laying beside me outside the safe (was cleaning). All parts assemblies.