With my 950, I use PLII and CES for pretty much any two-channel source except CD's - both TV viewing and DVD's with 2.0 soundtracks. I listen to CD's in straight stereo. Dolby 5.1 and DTS 5.1 DVD's get CES applied to bring the surround back channels into play. DTS-ES discs (of which I have very few, maybe five titles total) get DTS-ES processing, but for Dolby EX I probably use CES instead of EX more often than not.