Bottom Line-Do A, C panels have poorer off viewing angles compared to S-panels and in general do the ln32a550 have poorer off viewing angles than the 650-850 series. I have a ln32a450 S=panel that has a better viewing angle than my new ln32a550 A-panel. I have read that The A-panel uses 8 bit screen and S-panel uses 10 bit screen

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic