I always thought so too about the LPCM since i don’t have an ac3 demodulator. But i watched the preservation with the Dolby EX track and it blows the 2 channel stereo mix away. It isn’t logical or scientific but i think it sounds better than the DTS cinema tracks and even the blu ray audio.
I’ve always preferred the sound quality of DTS more than Dolby. I wouldn’t think Dolby EX could stand even a glimmer of chance against Blu-ray’s uncompressed audio tracks.