In most electronics today, performance and power-efficiency are the underlying factors of success. Similarly, the smartphone needs to be more power-efficient and performance oriented. No power-user can deny that Samsung has lead in this by a long margin.Also the latest Exynos chipset, packed in S6 and S6 Edge, also has sheer performance as compared to its competition.  Recent rumors are Samsung has something even better than this in store now. According to unofficial sources the next Exynos will pack custom cores, rather thanthe stock Cortex A72 silicon.The new SoC is allegedly codenamed "Mongoose" and will be humming at 2.3 GHz. A single-core Geekbench score is also in rumors. The number is around 2200, which is about 45% better than the current Exynos.   Now if the rumors are true then we will see the custom Exynos in next Galaxy Note and S seriesbut still raw power cannot be matched to real world performance. Let’s see how it performs when it gets into cutomers’ hands.