I have no idea what checksums have to do with it. Where did you by it? Ask the shop, they usually only stock one type. In fact all the panels in New Zealand, where I live, are the `C` panel. I haven`t seen an `S` panel, so I can`t compare, but I see nothing wrong with the `C` panel I have.
22"WS Samsung (LTM220M1-L01), or AU Optronics (M220EW01 V0), or CMO (M220Z1-L03), or CPT (CLAA201WA04) TN Film Who cares, it's a TN panel that aren't great anyway.
Depends...TN Panels are better for gaming...at least with their lower response timings. The 226BW is a great panel...I wouldn't recommend it for design purposes, though.
my above link tells you how to open the service screen and read which panel manufacturerer made your panel.