“Proper” reasons compared to other releases as of posting
01: E01-06 aired with wonky per field scaling causing severe artifacts and aliasing/jaggies, this version processes this correctly unlike the other releases.
02: CMS releases which has the best subs are for the most part sourced from KBS which has inferior broadcast quality compared to TVS due to mpeg2 artifacts, sharpness and network tickers, these are all sourced off TVS.
03: Since cap from 2 channels are available, a logo mask is used to fill the logo, removing it completely with no artifacts.
04: CMS release is slightly over filtered causing decimation of texture detail, this version has no texture loss.
Scripts taken from CMS.

CMS vs. DeenPolice
http://screenshotcomparison.com/comparison/113824/