Samsung Exynos 7420 Advantages
Larger memory bandwidth (24.8GB/s vs 13.9GB/s)
Qualcomm Snapdragon 660 Advantages
Better graphics card performance FLOPS (0.2176 TFLOPS vs 0.1976 TFLOPS )
Higher Frequency (2200MHz vs 2100MHz)
Lower TDP (5W vs 7W)
Released 2 years and 1 months late