Looking at a complete BCM lower to SBR and pair with the Kino currently residing on a PSA lower.

Is there a good reason to go with the A5 system, specifically for use with a 12.5”? I’m really not looking to tweak things as seriously as some do, at least not with this carbine. I consider this my rocksolid, any-purpose rifle that should always go bang with any ammo or situation. Are there advantages to running the A5 vs a standard carbine with an H2 or H buffer?