Understand, such comparisons between surround audio tracks are rarely w/o the element of subjectivity. Your assertion that .."DTS overall, has beaten Dolby in every category.." would probably make some hardcore HT enthusiasts/audiophiles chuckle. FWIW, I've heard great and poor examples of both ;).
Let's get back to something which is not at all subjective. Keep in mind that Pro Logic is not a HD (wideband) codec itself, but a type of enhancement. Pro Logic IIz is still a type of matrixed sound. I would probably stick with standard HD processing on its own since it's normally quite impressive, although the extra two speakers you add w/ IIz are supposed to be non-directional. To be honest proper speaker placement goes a long way to enhance what most folks already have, but haven't yet put much time into tweaking ;). IME even doing simple things like relocating a sub or adding a 8x10' area rug can really improve the sound of a HT space.
Then there's remembering that for extra speakers to work, the AV receiver has to have proper amplification for the extra speakers. Some good stuff @ about dot com on this here:
Some addtl. reading for you on the various formats:
I am buying a new HD surround sound receiver. After extensive testing and listening, I have found, as well as many others, proven rewards and comparisons that there is no doubt DTS HD Master Audio beats Dolby Tru HD hands down. Even when I was using a television with just 2 speakers, the voices sounded much more clear on DTS sound than with Dolby, which proves DTS is more refined with voice, midrange and sound effects including bass. And DTS HD Master Audio, as well as DTS overall, has beaten Dolby in every category, no offense to Dolby who has innovated so much. But sorry Dolby, you got beat, and this is why many Blu Ray discs only include DTS HD Master Audio for good reason. However, I have seen the innovation by Dolby Pro Logic IIz that uses surround front height speakers that are placed up high on the front wall in promixity to the front speakers aimed down towards the listener, and are supposed to add realism over the general 5.1 or 7.1 surround setup to make it sound like it really is raining in your room right above you and all around you, for example. I do not know much about IIz, but I do remember Pro Logic, not a truly digital format, so I am wondering how IIz is in relation to the HD digital formats, and if it will work with DTS HD Master Audio, and if it messes with the sound, being that it is not from Dolby, and if it is even worth using and buying the extra 2 speakers? Many viewers said the latest Star Trek movie only included Dolby Tru HD, and they said it did not sound that great in comparison to when it is displayed in DTS HD Master Audion. I need an experienced and qualified person to answer this please. Thank you.