I have both the C10 and the S10, I posted my observations a few months back and just to re-quote:
"Comparing the 42S10 to the C10:
Xbox360/PS3:
Connecting an Xbox 360 via components; Set at 720p for the C10 and S10, playing Street Fighter 4... While watching the demo I noticed the Street Fighter logo was surprisingly crisper on the C10 over the S10. Going over the PS3 set at 720p for both models, and playing my wife's Japanese game called "RailFan", both models handled the heavy train HD game footage very well. Finally, I tested "Ninja Gaiden" running 1080p for the S10, while we settled for 720p on the C10 (PS3). Over-all, the C10 was sharper and frustratingly better defined.
DVD:
Using a Pioneer DV-410v set at 1080p (Limited RGB), playing "I'AM LEGEND". The S10 came off with good colors along with the C10, but the S10 was a bit too soft for me (lacks a certain punch).
Blu-Ray:
Using a PS3 set at 1080p for both the S10 and the C10 gave mixed results:
-With a new movie like "The Dark Knight", both the S10 and the C10 gave very good picture quality. The S10 with it's 1080 moving resolution bested the C10 in the area of motion flow.
-Popping an old and somewhat poor transfer like "Bram Stockers: Dracula", delivered varied results for me. The S10 came off flat, soft and somewhat dull. The C10's inherently "glossy" pic (thanks to the reflective screen), gave a more "high-def" look with colors that seem to be more alive.
So far, the S10 remains the "weaker" of the Panny 2009 offerings in my possession...My brain can't accept what my eyes are telling me, so I may do another round"Presently with the 2009 models I have (G11,C10,S10) the S10, for me, was the "weakest" of the bunch, despite the bannered 1080p flash!
The G series on the other hand is a clear winner:
http://www.pinoydvd.com/index.php?topic=98930.120