Most of the time, any difference between Dolby and DTS on home video will have absolutely nothing to do with the codecs themselves. They will nearly always result from differences in the mixes used, or the average volume level at which the tracks are encoded. Dolby also forcibly engages dynamic range compression when downmixing 5.1 tracks to a lesser number of speakers, which creates a startling reduction in peak volume that makes it seem inferior when compared to DTS, which does not do this. Taken side by side on a full 5.1 setup, identical mixes encoded into Dolby and DTS formats will display nearly no difference whatsoever, aside from whatever minor improvements may result from using higher bitrates.
With both companies offering high resolution lossless options on Bluray, there is virtually no distinction between them aside from the technical issues of how the audio is actually stored and encoded and so forth.
It is the height of foolishness to judge the codecs based on inadequate criteria, and without taking other factors into consideration. Yet the pointless debate goes ever on . . .