In the short, big/little is crap, in theory it should have way better efficiency, but in the practice big/little doesn't work that way, it only supplements MT workloads. It would be better to have fewer big cores than combination of big/little because big cores if tuned correctly are very efficient in light workload, and also less latency which benefits games, not to mention how easier is to optimise software for all same cores design. I say from the beginning that big/little should be erased from the desktop PC. 3D stacking cores isn't far away, and as soon they start using it, no one would need to create small cores.