I am building a 12.5" 5.56 Pistol as a general purpose rifle on a LMT platform.  Reliability and accuracy are the priority, I would like to save weight but I'm willing to sacrifice that a little.  I know I need to have the barrel machine to fit the MRP-L upper.  Mid vs carbine length due to dwell time, it will host a HUX FLOW 556k suppressor and have a VLTOR A5 buffer with the Geissele Super 42 spring and have the LMT enhanced BCG.
I have narrowed down the barrels to the following options and would like your opinion and possible pros and cons. Other barrel options are welcomed!
*Faxon Duty Series 12.5" Gunner, Mid-Length, 4150 QPQ Nitride 556
*Rosco K9 12.5? Sage Dynamics, Gunner Gas length (in between carbine and mid-length)
*Criterion Barrels AR-15 CORE SERIES 12.5", CARBINE GAS
*12.3" 5.56 Ballistic Advantage HANSON CARBINE LENGTH Preference Series

Why not the LMT barrel?

Well now ya went and done it, ha.  Waiting for the 5th option to show up in the poll

Doubt many people could tell the difference shooting them all side by side.

Of those options - Criterion.

Why do you like this opinion?

It's a great barrel. It has a logical profile. It's chrome lined. I can tell you from first hand experience that they're well gassed. Not saying the others won't huck chunks of lead out of the end, but I dont think they're in the same category.

Sounds like you’re spending some money on the build.  I’d skip them all and go Centurion CHF.  I have the “LW” profile barrel which seems like more of a mid road between gov and lw.  Fit and finish is excellent.  It has an appropriately sized gas port.  Plus the tabbed gas block configuration adds a little security and goes together well.

https://centurionarms.com/lightweight-hammer-forged-barrel-carbine/

I had a 12.5" Criterion Core. I shot well and was gassed nicely for unsuppressed shooting. I replaced it with a Geissele CHF 12.5" barrel. It's a little more gassy, but I am running a BRT tube. It does seem to shoot a little better than my Core did. The upper is also now 100% Geissele.

I agree. I put a Centurion barrel in my main rifle and am thrilled.

I was just shopping for bbls as well. Have you looked at Wilson Combat bbls?

I've had 3 of the 4, not a rosco. Out of the 3 the criterion was a tack driver.

I have a Centurion barrel in my main AR, a BCA in my SBR & a Faxon gunner in a 16" AR

The bullet goes where I want with all of them. My vote is Centurion barrel since that is what I put in my main AR

Noveske 12.5 would be my choice.

Very happy with my 12.5" Criterion Core

Criterion barrels are a good bang for the buck. The profile of the core series makes the rifle feel like you're shooting a shorter barrel. The chrome lining ensures a long barrel life and they are as accurate as you would need them to be on a fighting rifle.

I get good velocity as compared to ballistic advantage and the accuracy seems to be less affected by heat brought on by hard use.