The MediaTek MT8389 is being used in a lot of Chinese tablets, and so is the new Allwinner A31s. First, let us see how MediaTek MT8389 and AllWinner A31S compare.
CPU MT8389 A31S
Tech 28 nm 40 nm
Base A7 A7
Clock 1.2GHz 1 GHz
RAM 1GB 1GB
GPU SGX544 SGX544MP2
Cache 1MB 1MB
Record 1080p 4K
To put simply, the processing technology and high clock speed makes the MT8389 better than the A31S. Processing tech has direct impact on battery consumption as 28nm will generate less heat than 40nm CPU and is more efficient too.
However, benchmarks tell a different story. Allwinner is more than 4000 points more than Mediatek CPU (see the top most picture). We are being told that it is due to overclocked GPU in Allwinner.
Same is the case in CF-bench benchmark test.
Real world performance is a different story though. For instance, in browser performance, MT8389 tablet browed the web a lot better than A31S. Pages load faster; pin and zoom frame rates are better and so on.
Video performance is better on A31 as it supports 4K video decoding. That said, since most of the videos you will be watching on it will be 720p or 1080p, you will not face any playback problems with either.