I’m going with an adjustable gas block so I can tune everything but not sure what the ideal options are.  Superlative, Seekins, and Odin pop up frequently but I’m not sure how to differentiate the marketing stuff vice how each relates to accuracy.  

Of course, I may simply be overthinking everything.  

Thanks for any thoughts.

I have a superlative on my .308 rig. It works. Only negative I have to say is that it requires an allen key to adjust, and with a carbine length gas system and a full length free float it's a bitch to adjust. Not Superlatives fault. More mine for setting the rifle up that way.

I'm curious as I'm looking to get another for a 6.5CM upper

I have an SLR adjustable (sentry 7?). Actually, I have them on most of my ARs. They require an Allen wrench as well. But, I use the Magpul K2 grip and the Allen wrench *just* fits in the grip compartment.

Aero precision makes a nice adjustable gas block. I’ve used them on 2 builds, haven’t had any problems and at $65 they’re priced right.

Superlative Arms

Superlative on mine as well.

I have Superlative on mine.

Superlative arms.   They include a long allen wrench with the gas block.   I have them on 2 builds and have had no problems with them.

Have a Superlative on my .308.  It does the job.

I just bought a $59 Seekins basic, no frills adjustable.  I'll be installing it tomorrow in my Lilja barreled .223 Wylde precision build.  That barrel comes with a hoggishly large .080" carbine gas port.  Even so, the barrel is sub 1/2 MOA capable.

I've been controlling the overgassed cycling with an H3 buffer.  My match loads are also not full 5.56 power, so that had helped.  Since the rifle will not see high or sustained rate of fire, the basic adjustable Seekins will hopefully serve well.  I, too, don't yet know how the Allen screw adjuster will line up under my rail.  I hope I can reach it with the key.  Its not the "click" or ratchet adjustment type.  Rather its a one time adjust, set, lock, and leave alone design.

I'll tune it for the match loads.  Just gas enough to cycle and hold the bolt back on an empty mag.   Might still be snappy for 5.56 NATO, but I don't shoot much of it in that barrel.  Might go back to a carbine gas buffer for the tuning.

We'll see how it goes.

Edit:  My rail blocks access to the Seekins gas adjustment screw.  My work-around was to use the shank of a 1/16" drill bit, .0625" placed in the Seekins port before installing on the journal and adjust the set screw up against the bit shank and then lock it down.  After assembling everything, retiming my muzzle device, I test fired with my lowest powered ammo.  Locks back fine and ejects at 3 o'clock.  Much improved.  I'll call this a win.