Qualcomm Snapdragon 425 Advantages
Lower TDP (5W vs 7W)
Released 10 months late
Samsung Exynos 7420 Advantages
Better graphics card performance FLOPS (0.1976 TFLOPS vs 0.024 TFLOPS )
Larger memory bandwidth (24.8GB/s vs 5.34GB/s)
Higher Frequency (2100MHz vs 1400MHz)
More modern manufacturing process (14nm vs 28nm)