6.2 has been doing great. The 6speeds were a touch quicker but the 8 speed is procuding better drivability and mpg. The 2014 6.2s were the same HP/TQ at 420/460. Car and driver late last year went 14.1@100 in a loaded to the hilt high country (King Rach) 4x4 crew cab truck. There are more than a few members on the forums going 13.9s in them in very good air. Pretty damn solid.