I have the xXx Superbit. The DTS track, while good, still to me lacked the overall impact of the theatrical Dolby Digital I saw. I mean, I did see it in a really well tuned cinema, but still, nothing has yet to match just how good that mix was.
I'd love to get the cinema DTS disc synced to the Blu-ray and compare.
The AC3 track from the DVDs was pathetic.