When watching 24 in dolby digital I'm looking to use all speakers in a 7.1 setup. I have heard that dolby pl2x can upconvert 5.1 sources to 7.1. How about dts neo 6? I'm running a onkyo 876 and it lets me run thx cinima with a dolby digital source and neo6. What is a better mode to use neo6 or pl2x?