I went the 1-4X route on a 18" JP CTR02. I use the gun for 3gun as well as defense. The JP gives me a rifle length gas system, adj. gas block, lightened bolt carrier and comp to make a really soft/flat/accurate shooting rifle. However, due to JP's bbl profile the rifle is not heavy at all and balances real well.

I put the NF 2.5-10X32 on a Savage Mdl. 10PC (precision carbine) in .308 (accutrigger and accustock). The bbl. on my savage had been cut back to 18" and threaded by first owner. I put a comp on it and it worked out great. I like my combo- Med weight AR with 1-4X and a more precision short bolt gun in larger .308cal w/ larger magnified optic that shoots lights out and is still easy to carry/shoot. Going the bolt gun route vs. gas gun in .308 saved a boat load of cash that could be spent on other gear, ammo, etc. My .02