Shot the Ruger SFAR 308 (finally). I like it. I had feed issues with the H2 buffer I installed (in order to reduce recoil), but fortunately I predicted this and had the standard carbine 3oz with me. All went well after that, but I don't like the very high strength buffer spring that Ruger provided. I think it's a problem, especially if rounds are not cycling properly with the bolt trapping the cartridge while feeding. In other words, the rearward travel is not far enough. It works fine at the max gas setting, but the recoil is not very friendly with that. So now I'll try playing with buffer springs to see if I have better luck. I ordered a flat wound spring from Strike Industries and will use that in conjunction with heavier buffers to reduce cycling speed as needed.
Overall, the SFAR is wildly awesome. Feels like an AR15 at 6.8 lbs, yet slings a 308 boolit. Nice.