Here is the scenario: I want to build an SPR AR and basically have 2 options on an upper that I will build it off of.

Option 1:
I have a 20" 1/7 twist, standard government BCM upper, which I can send off to ADCO and for $287 can have the front post shaved down and have Troy TRX 13" Free-float rails installed. From this point on I am already set as far as which Bipod, Scope, Scope mount, and stock. This route would run my roughly $1,990.

Option 2:
I can sell my 20" BCM upper to a friend for somewhere between $250 and $300, so I'll just split the difference and say $275. Then I can order from BCM an SPR Mk 12 Mod 2 Bravo upper which has a low pro gasblock, the stainless SS410 18" 1/8 twist barrel, and LaRue 12" Free-float rails. This route with the same accessories as option 1 would cost about $2400.

Basically what I am wondering is will it be worth the extra $410 for the upgraded barrel and "better" handguards? I'm not too familiar with the technical benefits of the SS410 1/8 twist 18" barrel over a standard that is 2" longer...so any opinions would be appreciated.

Thanks, Plumber