Re: PS3 as a Blu Ray -- Question
If you really wanted to improve the look of things in terms of video scaling - you might look at a DVDO VP50pro. I would run it HDMI without question.
ALSO - don't use cheap cables. You don't have to break the bank. Look into Accel, Ultralink and Transparent's basic cables. Even as analog cables - these will provide a notable improvment for high res sources.
Jerry Del Colliano